Why do people think Alu frames are HARSHER?
alan
Of course, Alu frames are STIFFER because of the larger tubes, etc.
Let's not discuss this. I read in the FAQ that frame deflections are
very small compared to tires, etc. Yet thousands of MTBers complain
about the HARSHNESS of Alu frames. Are thousands of MTBers with
thousands of sore hands and butts wrong? I don't think that a test
which measures static deflections between steel and Alu frames explains
this away. I'm also skeptical that Alu frames ONLY feel stiffer/harsher
because they make a higher pitched sound, and thus it's only an acoustic
effect. Yesterday, I test rode a Specialized M2, and I felt more rear
wheel shock through the handlebar than my steel bike. Has anybody done
a test where a steel and Alu frame (with identical tires, etc) were
subjected to realistic trail shocks, and a frequency spectrum was taken
at the handlebars, pedals and seat?
ACF
Jim Frost
> I read in the FAQ that frame deflections are
> very small compared to tires, etc. Yet thousands of MTBers complain
> about the HARSHNESS of Alu frames. Are thousands of MTBers with
> thousands of sore hands and butts wrong?
I don't think that many thousands of riders (not just MTBers) are wrong
in claiming that there's a difference in feel between the two
materials. But they may well be wrong about the reason for the
difference.
It can't be a matter of tube stiffness. Thin tubed Al bikes are
anything but stiff, but people still complain about them. My personal
theory is that Al probably is much more efficient at transmission of
high-frequency vibrations than is steel, though I have absolutely no
data to back this up.
jim frost
ji...@world.std.com
Anthony Levand
alan <jsb...@uclink2.berkeley.eduREMOVE> wrote in article
<33DE77...@uclink2.berkeley.eduREMOVE>...
> Of course, Alu frames are STIFFER because of the larger tubes, etc.
> Let's not discuss this. I read in the FAQ that frame deflections are
> very small compared to tires, etc. Yet thousands of MTBers complain
> about the HARSHNESS of Alu frames. Are thousands of MTBers with
> thousands of sore hands and butts wrong? I don't think that a test
> which measures static deflections between steel and Alu frames explains
> this away. I'm also skeptical that Alu frames ONLY feel stiffer/harsher
> because they make a higher pitched sound, and thus it's only an acoustic
> effect. Yesterday, I test rode a Specialized M2, and I felt more rear
> wheel shock through the handlebar than my steel bike. Has anybody done
> a test where a steel and Alu frame (with identical tires, etc) were
> subjected to realistic trail shocks, and a frequency spectrum was taken
> at the handlebars, pedals and seat?
>
> ACF
>
I don't know if aluminum frames are stiffer or not. The elastic modulus of
aluminum is 1/3 of steel. The torsional and bending stiffness of a tube
varies with the diameter cubed. However in a diamond frame act as a truss
and load is carried uniaxially and thus stiffness varies only by area, or
diameter squared. For an equally stiff aluminum frame would have the same
weight as steel in tension or compression.
Tony
John Connolly
alan wrote:
>
> Of course, Alu frames are STIFFER because of the larger tubes, etc.
> Let's not discuss this. I read in the FAQ that frame deflections are
> very small compared to tires, etc. Yet thousands of MTBers complain
> about the HARSHNESS of Alu frames. Are thousands of MTBers with
> thousands of sore hands and butts wrong? I don't think that a test
> which measures static deflections between steel and Alu frames explains
> this away. I'm also skeptical that Alu frames ONLY feel stiffer/harsher
> because they make a higher pitched sound, and thus it's only an acoustic
> effect. Yesterday, I test rode a Specialized M2, and I felt more rear
> wheel shock through the handlebar than my steel bike. Has anybody done
> a test where a steel and Alu frame (with identical tires, etc) were
> subjected to realistic trail shocks, and a frequency spectrum was taken
> at the handlebars, pedals and seat?
>
> ACF
I DO know that a ways back, skateboards went thru an aluminum
phase...for the decks... and riders had a problem with their feet and
ankles getting real tired... maybe it isn't a shock problem, but a
resonance problem...
From what I understand though, some of the newer aluminum frames have a
good deal of flex designed into em' anyways; a hell of a lot more than
the older ones......
I don't know, I am just raising this subject up for discussion...
John
g.m.
In article <33DE77...@uclink2.berkeley.eduREMOVE>, alan
<jsb...@uclink2.berkeley.eduREMOVE> wrote:
> Of course, Alu frames are STIFFER because of the larger tubes, etc.
> Let's not discuss this. I read in the FAQ that frame deflections are
> very small compared to tires, etc. Yet thousands of MTBers complain
> about the HARSHNESS of Alu frames.
not in my case..i ride a mongoose alta sx and it's a lot more smooth to
ride than my roadie... my butt is also happier on the mongoose..
gm
Rick Denney
The stiffness of tubes has much more to do with cross-section than
material. Aluminum is not as strong as steel, but it is stiffer in
relation to its strength. Aluminum frames are usually designed with
larger tubes to allow a stronger design without adding weight, such as
Klein and Cannondale. This makes the frames stiffer. Most newer makers
make use design tricks to minimize this effect. For example, many
aluminum bikes use ovalized tubes to reduce the stiffness in directions
where they are not needed.
But recognize that the truss design of frames means that very little
vertical flex comes from the diamond. Much of what I feel as stiffness
seems to come through the handlebar and the pedals rather than the
saddle. Metallic bikes with extreme lateral stiffness in the bottom
bracket because of very oversize tubes wear me out much more than bikes
with a little flexibility down there. My OCLV is very stiff, but the
plastic is not as elastic, and absorbs energy instead of transmitting
all of it (actually, it absorbs energy and then gives it back more
slowly. Metal bikes give it back more quickly). My steel bikes have more
noticeable flex, and they are more comfortable still. My only aluminum
bike is my Homegrown, and the suspension fork and fat tires absorb much
more than anything a road bike could.
alan wrote:
>
> Of course, Alu frames are STIFFER because of the larger tubes, etc.
> Let's not discuss this. I read in the FAQ that frame deflections are
> very small compared to tires, etc. Yet thousands of MTBers complain
Garry Lee
People find them harsher because they expect to.
I can remember reading an article maybe 12 years ago when an
expert(!) said that there was nothing like aluminium to absorb shock!.
It's all nonsense. You cannot tell the difference, unless you stand
up, and some steel bikes are just as laterally stiff.
Tom Ace
Why do people think aluminum frames give a harsh ride?
I think part of it started out as a sour-grapes thing. I bought a
Cannondale frame the first year they were on the market (mid 1980s)
and I heard all kinds of things from other cyclists. I heard the fat
tubes were ugly, I heard the welds were sloppy, I heard they looked
stupid because tubes were bowed after heat treatment, and I heard they
had a harsh ride. Many of these remarks came from racer-types who in
general worshipped at the altar of stiffness, and although they
coveted the rigidity of fat-tubed aluminum frames they badmouthed
them to no end (unless they owned one).
Tom Ace
cr...@best.com
hau...@mbi.org
In article <timmcn-3107...@dialup-67.minn.net> tim...@minn.net (Tim McNamara) writes:
>From: tim...@minn.net (Tim McNamara)
>Subject: Re: Why do people think Alu frames are HARSHER?
>Date: Thu, 31 Jul 1997 12:57:44 -0600
Tim wrote:
>Frame stiffness is more a function of frame design than material.
>Aluminum frames can be designed to be fairly soft and forgiving (e.g.,
>Alan cyclo-cross frames or Vitus 979 road frame) or stiff and harsh (e.g.,
>Klein).
Then he wrote:
>Basically, the myth that aluminum frames are harsher comes from people
>like bike shop mechanics amd magazine writers being clueless about frame
>design and material characteristics.
Well, I'm confused. Is a Klein harsh or isn't it?
Rich
Tim McNamara
"Harsh" is hard to quantify; however, *I* find Kleins to be very harsh and
stiff. Others may find them "precise and responsive;" it's a matter of
taste to a large degree. My personal preference is a slightly more
flexible frame made of steel (I've never had a chance to ride Ti) because
I find it less tiring over a long ride. Other people I know do centuries
on Kleins and Cannondales frequently and love the ride of their bikes.
OTOH, Sean Kelly won hundreds of races on aluminum Vitus 979's, which were
reknowned for being as stiff as al dente pasta.
Stiffness in a Klein is due to its being built with oversized diameter
tubing in the main triangle and rear triangle, steep seat tube and head
tube angles and extremely short chain stays. A Klein is stiff because of
the frame design, not the mere fact that it's built out of aluminum
tubing. A steel bike built to the same specs would also be "stiff" or
"harsh." Stiffness in tubing made from any material can be increased by
making the walls thicker, increasing the diameter of the tubing or
shortening the tube (or all three at the same time). Vitus 979's were
made of nearly standard diameter aluminum tubing and as a result were
quite flexible (at any given thickness, aluminum is actually less stiff
than steel; that's why modern aluminum frames are built with oversize
tubing).
BTW, aluminum frames tend to be designed to be stiff because of the
fatigue characteristics of aluminum. Flexible aluminum frames tend to
suffer fatigue failures fairly quickly, so a non-flexible frame is
supposed to live longer before it fails. Ti frames, on the other hand,
can be built more flexibly because that material has excellent fatigue
characteristics- although despite the hype Ti is indeed breakable. So is
steel.
All three are viable choices for bicycle frames (and we haven't even
discussed carbon fiber) and great bikes can be made from each. Aluminum
seems to be the metal of choice for mountain bikes and cyclo-cross; it is
also much more popular in the Euro-pro peloton than it used to be, looking
at the photos. My contention, however, is that ride characteristics are
predominantly determined by frame design and not by material used.
--
All I leave behind me is only what I've found.
-Robert Hunter
Tim McNamara
Frame stiffness is more a function of frame design than material.
Aluminum frames can be designed to be fairly soft and forgiving (e.g.,
Alan cyclo-cross frames or Vitus 979 road frame) or stiff and harsh (e.g.,
are misattributing the quality of the ride to the material; it's actually
the frame design.
Shorter tubes are stiffer (e.g., short chain and seat stays make for a
stiffer back end); fatter tubes are stiffer; tubes with thicker walls are
stiffer. Mountain bikes are usually designed with small frames and a
sloping top tube, tending to make the main triangle stiffer. The chain
and seat stays tend to be fatter, increasing stiffness. Forks tend to be
sloppy because of the inherent problems with telescoping forks and small
diameter front hub axles/retaining systems (that and the fact that bicycle
suspension forks are mostly built upside down, as compared to the
motorcycle fork).
Basically, the myth that aluminum frames are harsher comes from people
like bike shop mechanics amd magazine writers being clueless about frame
design and material characteristics. And why not? That's what engineers
are for in the first place. *They* have to understand this stuff. If
they do their jobs, riders can just ride.
Dave Blake
alan wrote:
>
> Of course, Alu frames are STIFFER because of the larger tubes, etc.
> Let's not discuss this. I read in the FAQ that frame deflections are
> very small compared to tires, etc. Yet thousands of MTBers complain
> about the HARSHNESS of Alu frames. Are thousands of MTBers with
> thousands of sore hands and butts wrong? I don't think that a test
> which measures static deflections between steel and Alu frames explains
> this away. I'm also skeptical that Alu frames ONLY feel stiffer/harsher
> because they make a higher pitched sound, and thus it's only an acoustic
> effect. Yesterday, I test rode a Specialized M2, and I felt more rear
> wheel shock through the handlebar than my steel bike. Has anybody done
> a test where a steel and Alu frame (with identical tires, etc) were
> subjected to realistic trail shocks, and a frequency spectrum was taken
> at the handlebars, pedals and seat?
>
> ACF
Aluminum is a very soft metal compared to steel. For a given
geometry aluminum will always be much softer than steel,
in terms of elastic modulus.
Some aluminum frame makers, like Cannondale, use oversized tubing.
The tubing is still very soft compared to a comparable steel
oversized tubing, but stiff compared to narrow aluminum tubing.
In fact, measured vertical or torsional stiffness of
the Cannondales shows them to be among the stiffest frames.
But vertical compliance is simply too small compared even
to road bike tire, wheel, and fork flex.
It is likely that other parameters affect the judgment.
For example, some frame makers think that lowering the
seatstay/seat tube intersection makes the ride more
comfortable. Some think that positioning the rider further
forward relative to the rear wheel (longer chainstays) is
more comfortable. Aluminum frames are almost never the
same geometry as steel frames, so it is hard to even
compare.
Lastly, there are psychological concerns. It has been
demonstrated that one of the strongest factors in ride
comfort in a car is vehicle noise. If a vehicle is nearly
silent it is perceived as a smooth ride independently of
the physical smoothness of the ride. Aluminum oversized
tubing has different auditory characteristics than
narrower steel tubing.
--
Dave Blake
dbl...@phy.ucsf.edu
http://www.keck.ucsf.edu/~dblake/
hau...@mbi.org
In article <5rpdrh$4jv$3...@nuacht.iol.ie> Garry Lee <gl...@iol.ie> writes:
>From: Garry Lee <gl...@iol.ie>
>Subject: Re: Why do people think Alu frames are HARSHER?
>People find them harsher because they expect to.
>I can remember reading an article maybe 12 years ago when an
>expert(!) said that there was nothing like aluminium to absorb shock!.
And this is really the crux of the issue. Those who don't know better listen
to hearsay and it becomes their own gospel. Those of us who have lots of
experience with both, AND have a brain, know better.
Thanks, Garry, for spelling it out.
Rich
hau...@mbi.org
In article <timmcn-3107...@dialup-176.minn.net> tim...@minn.net (Tim McNamara) writes:
>From: tim...@minn.net (Tim McNamara)
Tim wrote:
>"Harsh" is hard to quantify; however, *I* find Kleins to be very harsh and
>stiff. Others may find them "precise and responsive;"
That would be my opinion. It's really pretty interesting to hear such
opinions, though, since responsiveness IS a primary frame function, whereas
ride 'harshness' or lack thereof is NOT.
>Stiffness in a Klein is due to its being built with oversized diameter
>tubing in the main triangle and rear triangle, steep seat tube and head
>tube angles and extremely short chain stays.
Not quite. My klein has the usual stage/touring 72 degree head angle, and
unusually LONG chainstays. Even the quantum pro has normal racing length
chain stays. The ATB Kleins are known partially for their square chainstays,
but again, they're not unusually short - and certainly not 'extremely' short.
On the contrary, Klein was a pioneer in designing stock frames that actually
fit people. Thus, his small frames have short top tubes, and his big ones
have long ones. His large touring frames actually have wheelbases around 43
inches (!), which is the way it should be.
A Klein is stiff because of
>the frame design, not the mere fact that it's built out of aluminum
>tubing. A steel bike built to the same specs would also be "stiff" or
>"harsh."
Well, this is really the critical point. You use the two terms
interchangeably, but generally those who criticize an OAF (oversized aluminum
frame) for being 'harsh' consider it a bad trait, whereas stiffness (ie
efficiency or responsiveness) is a good trait.
My contention has always been that stiffness does not necessarily mean harsh.
Ride quality is affected more by the wheels and tires (in most cases, MUCH
more) than by the frame (with obvious exceptions being suspended frames).
Stiffness in tubing made from any material can be increased by
>making the walls thicker, increasing the diameter of the tubing or
>shortening the tube (or all three at the same time). Vitus 979's were
>made of nearly standard diameter aluminum tubing and as a result were
>quite flexible (at any given thickness, aluminum is actually less stiff
>than steel;
Actually aluminum is about 1/3 the stiffness, 1/3 the weight, and 1/3 the
strength of steel. I don't think that's any secret. What doesn't seem to be
well-understood, though, is that titanium is about 60% the weight and
stiffness of steel. Thus, replacing aluminum with titanium adds weight - it
doesn't subtract it. This feeling that titanium is somehow stronger than
steel, yet lighter than aluminum still seems to exist. I suspect that people
attempt to justify the price by attributing magical qualities to it. In
reality, though, titanium is simply a stepping stone between the two less
costly metals; thus, a titanium frame should be slightly oversized, as
compared to a traditional steel frame.
Rich
alex wetmore
Tim McNamara <tim...@minn.net> wrote in article
<timmcn-3107...@dialup-176.minn.net>...
> Stiffness in a Klein is due to its being built with oversized diameter
> tubing in the main triangle and rear triangle, steep seat tube and head
> the frame design, not the mere fact that it's built out of aluminum
> tubing. A steel bike built to the same specs would also be "stiff" or
> making the walls thicker, increasing the diameter of the tubing or
> shortening the tube (or all three at the same time).
Also, there are (or were, they aren't made any longer) Kleins out there
with the trademark oversized stiff tubing, but with much more relaxed frame
geometries. I have a Klein Performance from the mid 80s (don't know the
exact year, I am the 3rd person to own it) which has long chainstays
(longer then those on my Trek 520 touring bike) and a pretty relaxed head
angle. The wheelbase is long enough on it that it doesn't quite fit
properly into the bicycle racks on the buses in the Seattle area (both
wheels don't sit completely in the wheel holding area on these busses).
How does it ride? I'm not an expert racer, so I can't comment completely.
However, compared to my Trek 520 I find that its about as comfortable (the
slack angles and 28mm tires do more to help with this then the extra stiff
tubes could possibly hurt it). I think that its a little stiffer in the
bottom bracket, but this is probably a mental thing more then anything
(something has to be better about it, right?), so it sprints very well
(again, I don't race). It does weigh a few pounds less then my Trek 520
(it used to weigh a lot less, but then I put a rack and a Brooks saddle on
it).
Plus its got a lot of oddities which make you have to love it. Like the
downtube brazeons that aren't compatible with cable-stop adapters (I had to
add another set of downtube brazeons to get bar-end shifters on the bike),
rear-rack brazeons which are about 2" too high to use any racks on the
market, and two water bottle brazeons, but with the second under the
downtube, rather then on the seat-tube the way most second bottle brazeons
would be (usually you find the 3rd under the downtube).
alex
Timothy C. Stan
In article <5rq8na$1k...@itssrv1.ucsf.edu>,
dbl...@phy.ucsf.eduDELETETHISPART (Dave Blake) wrote:
>alan wrote:
>
>Aluminum is a very soft metal compared to steel. For a given
>geometry aluminum will always be much softer than steel,
>in terms of elastic modulus.
>
>Some aluminum frame makers, like Cannondale, use oversized tubing.
>The tubing is still very soft compared to a comparable steel
>oversized tubing, but stiff compared to narrow aluminum tubing.
>In fact, measured vertical or torsional stiffness of
>the Cannondales shows them to be among the stiffest frames.
>
>But vertical compliance is simply too small compared even
>to road bike tire, wheel, and fork flex.
>
>It is likely that other parameters affect the judgment.
>For example, some frame makers think that lowering the
>seatstay/seat tube intersection makes the ride more
>comfortable. Some think that positioning the rider further
>forward relative to the rear wheel (longer chainstays) is
>more comfortable. Aluminum frames are almost never the
>same geometry as steel frames, so it is hard to even
>compare.
>
Good stuff. Remember that when you're talking "Aluminum vs. Steel" you're talking about
materials. It is possible to make a flexible, noodley bike out of aluminum (i.e. Vitus --not a
slam, I like Vitus frames-- ). It is also possible to make a very stiff bike out of steel.
When comparing frame designs, you're comparing structures. Aluminum, because of its lighter
relative weight, allows engineers to make stiff structures without a big weight penalty. You
could make a bike frame out of oversized steel tubes and it would end up very stiff. However, it
would also be very heavy.
As far as frame stiffness goes, a frame should be stiff laterally so that the rider's pedaling
energy gets transmitted to the rear wheel efficiently, and is not soaked up by flexing the frame
back and forth. More flexible frames may have a slightly softer feel, but this is at the cost of
decreased efficiency. In any case, the components (wheels, tires, fork, handlebar, etc.) do much
more to soak up road shock than the frame does.
The question that always occurrs to me: If Cannondale frames are supposedly so harsh, why do so
many people do long-distance touring on them?
thanks,
Tim from Cannondale
PS: Yes, I work for Cannondale, so I'm a bit biased. Dialogue is always welcome, though.
Timothy C. Stan
>In article <5rpdrh$4jv$3...@nuacht.iol.ie> Garry Lee <gl...@iol.ie> writes:
>>From: Garry Lee <gl...@iol.ie>
>>Subject: Re: Why do people think Alu frames are HARSHER?
>>Date: 31 Jul 1997 07:11:45 GMT
>
>>People find them harsher because they expect to.
>>I can remember reading an article maybe 12 years ago when an
>>expert(!) said that there was nothing like aluminium to absorb shock!.
>
>And this is really the crux of the issue. Those who don't know better listen
>to hearsay and it becomes their own gospel. Those of us who have lots of
>experience with both, AND have a brain, know better.
>
>Thanks, Garry, for spelling it out.
>
>Rich
>
I think you've hit the nail on the head there. It reminds me of a study done a couple of years
ago comparing initial quality of new cars. In this study, owners of new Honda Passports reported
higher satisfaction with the quality of their new cars than did owners of new Isuzu Rodeos. The
Honda Passport is nothing more than a re-badged Isuzu Rodeo, so it would seem that the Honda
owners felt more satisfied with their vehicles because they expected to be more satisfied. I'm
sorry to blather on about cars in a bike newsgroup, but it just shows that people often see and
feel what they want to see and feel, rather than what is actually there.
Tim from Cannondale
Donald S. Finan
In article <33DEBA3D...@world.std.com>,
Jim Frost <ji...@world.std.com> wrote:
>> I read in the FAQ that frame deflections are
>> very small compared to tires, etc. Yet thousands of MTBers complain
>> about the HARSHNESS of Alu frames. Are thousands of MTBers with
>> thousands of sore hands and butts wrong?
>
>in claiming that there's a difference in feel between the two
>materials. But they may well be wrong about the reason for the
>difference.
>
>It can't be a matter of tube stiffness. Thin tubed Al bikes are
>anything but stiff, but people still complain about them. My personal
>theory is that Al probably is much more efficient at transmission of
>high-frequency vibrations than is steel, though I have absolutely no
>data to back this up.
>
I would think this is doubtful, considering that Aluminum is not as
stiff as steel.
--
==>====>====>====>====>====>====>====>====>====>====>====>====>====>====>==
Don Finan "A really hoopy frood who knows
dfi...@ucs.indiana.edu where his towel is."
==<====<====<====<====<====<====<====<====<====<====<====<====<====<====<==
Thomas H. Kunich
In article <NEWTNews.8707921...@pp000428.mindspring.com>,
000...@mindspring.com> wrote:
>My "oversized tube" titanium frame (Spectrum/Merlin) is rather
>compliant vertically and laterally. I've put over 19,000 miles on
>it in the last 3 years and find it quite comfortable, but I don't
>feel that the flex in the frame robs me of efficiency when I jump on
>it in a sprint. I thought this topic has been discussee ad nauseum
>in past threads and the general consensus was that this widely held
>belief is a myth. Care to comment Jobst? - Jim McNamara
OK, mechanical principles 101:
Tubing stiffness goes up with the cube of the diameter.
You can build light and VERY stiff structures out of virtually any
reasonable construction material. Even cardboard, believe it or not.
A roof collapsed with a load of 20,000 lb.s on it which fell down
on the interior cubicles. The cubicle dividers only crushed about
1/2 way and supported this tremedous load! Cubicle dividers are
cardboard honeycomb. Sections of material used in aircraft use
aluminum honeycomb that have paper thin aluminum in the interior
sections are extremely light and strong enough to walk on.
Aluminum, steel and titanium can all be used to construct frames
that are stiff or compliant.
It doesn't make any difference though. The stiffer the frame the
better it is. When you are flying down a hill at 45 mph and hitting
rough sections of road you DON'T want the bike changing directions
because of flex in the frame.
If you are having trouble with any specific frame being "too stiff"
(ain't no such thing) it is probably because the tires are too small
and the pressure is too high.
So why do carbon fiber and titanium buff claim that their frames feel
better? They don't, but one thing is that these materials don't have
natural oscillatory frequencies that can be excited by road conditions.
In other words, the frames don't 'ring' from road surface. This is
the same thing that steel frame buff find so attractive. One disadvantage
of steel frames is this natural frequency allows the frame to
turn into a spring on occassions and hop around on the road.
But when the frame is constructed with the proper sized tubing
for the size of the bike this doesn't occur.
In short: any frame can be a good frame built from any material. But
it is an individual thing that has to do with geometry of the bike,
the weightof the rider, the size of the tubing and the wheel and
tire combination on the finished bike.
For instance, I have had several problems with my Colnago Super getting
wobbles in fast downhills after hitting a Bot's Dot or some such.
I just had some problems with the wheels (American Classic hubs
and Campi Aero rims) and changed to my Mavic hubbed, Araya super
aero rims and the problem seems to have disappeared. The first
set have 23 mm Continental GP's while the second have 28 mm Avosets
(these are really only 25 mm).
My Eddy Merckx with oversized tubing (61 cm size frames mind you)
never has given a seconds scare. My Graftek carbon fiber, never.
Stiff is better, if you need compliance you get it from the tires.
Drew Eckhardt
In article <5s4rr6$9...@dfw-ixnews7.ix.netcom.com>,
Timothy C. Stan <tcs...@ix.netcom.com> wrote:
>The question that always occurrs to me: If Cannondale frames are supposedly
>so harsh, why do so many people do long-distance touring on them?
The same reson consumers buy other products - excellent marketting and
advertising, good brand recognition, plenty of retail outlets which makes
Cannodale products easy to purchase, and a distinctive design which sets
them appart from most of the competition mass-market bikes - all reasons
which have nothing to do with harshness or a lack thereof.
In other areas (high-end audio, Ben & Jerry's Cherry Garcia ice cream vs.
yogurt, etc), I've done blind A/B comparisons between various products. In
some cases, the blind results were the opposite of what we got with sighted
tests and our preferences changed, suggesting that our previous opinions had
been colored by our prejudices. In other cases, the results confirmed what
we already believed, or failed to show that differences existed.
Based on that, I accept that the harshness I've experienced riding aluminium
bikes (Cannondale, Giant, GT, Scott, Specialized, Trek) may come from me
experiencing what I expect to.
In double blind audio tests, we've found that distortions of under 1%
(-20dB) are detectable by many people. Some prefer them when they're of
the right harmonic content, and others always dislike them. Likewise, the
tiny portion of the total flex in a bicycle provided by the frame may be
quite significant with respect to "feel."
Until some one (any one from the big companies, or publications listening?)
gets one or more frame builders to throw together identical TIG welded
frames made from the different metals (titanium, aluminium, oversize steel),
paints them identically, builds them with identical components, and does a
double-blind comparison, it's silly to decide that people are experiencing
a placebo effect, or that aluminum frames are actually harsh.
However, given the price of bikes these days (starting at $1000-1500 for
what I'd consider a minimum "acceptable" quality road or mountain bike),
it's also ludicrous to risk our money when we don't know if aluminum
frames give a harsh ride.
--
"Come to the edge, Life said. They said: We are afraid. Come to the edge,
Life said. They came. Life pushed them...and they flew." -Guillaume Apollinaire
Work: dr...@Qualcomm.COM Play: dr...@PoohSticks.ORG
Home Page: <a href="http://www.poohsticks.org/drew/">Home Page</a>
Thomas H. Kunich
In article <NEWTNews.8708146...@pp000428.mindspring.com>,
<pp00...@mindspring.com> wrote:
>Perhaps someone will profit from this information with which I am
>already familiar. For the most part I am in agreement with you. I
>too ride a 61cm frame on 23mm Conti GPs, but unlike yourself, I find
>the compliance provided by my titanium frame to be welcome after
>being beaten to death for years on a less compliant steel frame.
My, my. A bit touchy after spending all that money on a bicycle?
Try riding one og those 'less compliant' stiff steel frames with
Jobst's favorite tires: Avocets, say 25 or 28 mm? Then tell us
about how compliant the ride is on the ti bike.
Now don't get me wrong. A titanium frame is nice. They will probably
last forever, they won't rust, they look cool, etc.
But if you bought it for the ride you did the wrong thing. And if
it rides well it's because everything came together properly
and that is generally luck aided by a century of trying to find
out what would work well.
So, how do you tell this "compliance" when the frame bends about
10% as much as the tires do?
DEMPSEY
to...@netcom.com (Thomas H. Kunich) writes:
>In article <NEWTNews.8707921...@pp000428.mindspring.com>,
>000...@mindspring.com> wrote:
>>My "oversized tube" titanium frame (Spectrum/Merlin) is rather
>>compliant vertically and laterally. I've put over 19,000 miles on
>>it in the last 3 years and find it quite comfortable, but I don't
>>feel that the flex in the frame robs me of efficiency when I jump on
>>it in a sprint. I thought this topic has been discussee ad nauseum
>>in past threads and the general consensus was that this widely held
>>belief is a myth. Care to comment Jobst? - Jim McNamara
>OK, mechanical principles 101:
What mechanical property is being described by 'stiffness' here?
Is a 1 1/8" O.D. tube with 1.055" I.D. more 'stiff' than a 1" O.D. tube with
0.5" I.D? Whatever you're trying to describe, and I'd suspect it's likely
a tube's rigidity, your description seems plenty too simple to offer any
insight into why people describe aluminum frames as 'harsh.' On the other
hand, maybe you're trying to make the point that cyclists do NOT know
anything about mechanical properties of tubing or structures, and that a
description of a bicycle as 'harsh' is no more meaningful than a description
of a bicycle as 'somewhat reddish.' If so, well done, you suckered me, too!
>Tubing stiffness goes up with the cube of the diameter.
>You can build light and VERY stiff structures out of virtually any
>reasonable construction material. Even cardboard, believe it or not.
>A roof collapsed with a load of 20,000 lb.s on it which fell down
>on the interior cubicles. The cubicle dividers only crushed about
>1/2 way and supported this tremedous load! Cubicle dividers are
>cardboard honeycomb. Sections of material used in aircraft use
>aluminum honeycomb that have paper thin aluminum in the interior
>sections are extremely light and strong enough to walk on.
Wow, so 'stiffness' is a measure of a structure's ability to not completely
crush while supporting a collapsed roof? What was the weight of that set of
interior cubicles? Something that light and 'stiff' should make a good
bicycle frame, eh? What are we talking here, 3 or 4 pounds of interior
cubicle material? What size bottom bracket shell fits in an interior cubicle
frame? What is the diameter of one of those interior cubicle bicycle frames,
so that we can cube it and set a benchmark for good 'stiffness?'
>Aluminum, steel and titanium can all be used to construct frames
>that are stiff or compliant.
I guess an interior cubicle bicycle frame is then 'half-stiff,' or is it
'half-compliant?' They crush only halfway, right?
>It doesn't make any difference though. The stiffer the frame the
>better it is. When you are flying down a hill at 45 mph and hitting
>rough sections of road you DON'T want the bike changing directions
>because of flex in the frame.
I'm coasting whenever I'm hitting 45 mph, but I'm pedalling pretty hard
sometimes at well under 10 mph while climbing on my mountain bike. Is it
O.K. for my frame to flex and, as you say, my bike changing directions, at
that point, you know, since I'm going so much slower? Are you saying that
one of those interior cubicle bicycle frames won't deflect under load, or am
I confusing that with what you're calling stiffness again? Boy, I just don't
understand, I thought they would crush halfway...
>If you are having trouble with any specific frame being "too stiff"
>(ain't no such thing) it is probably because the tires are too small
>and the pressure is too high.
I think the problem the rider was having was soreness in his body, is that
right? How does that relate to a falling roof again?
>So why do carbon fiber and titanium buff claim that their frames feel
>better? They don't, but one thing is that these materials don't have
>natural oscillatory frequencies that can be excited by road conditions.
>In other words, the frames don't 'ring' from road surface. This is
>the same thing that steel frame buff find so attractive. One disadvantage
>of steel frames is this natural frequency allows the frame to
>turn into a spring on occassions and hop around on the road.
Are you saying that the oscillations of a frame ringing at a frequency some-
where on the order of magnitude 1,000 - 10,000 Hz cause a frame to hop around
on the road? I can't imagine those oscillations having an amplitude anywhere
NEAR those required to make a bicycle built around it to change it's course
along a road, let alone lift its bare 3 or 4 pounds right off the road when
'rung.' I'm well aware of how frequent steel frames are spotted. Are interior
cubicle bicycle frames naturally frequent? I've never
even SEEN one, where do they breed?
>But when the frame is constructed with the proper sized tubing
>for the size of the bike this doesn't occur.
I'm 6'1" tall with a 33 1/2" inseam. What is the proper size tubing to use
for a steel frame that will remain on the ground when 'ringing' from the road
surface. This is important to me - I have NO kickstands available and live
VERY close to a set of train tracks, and you know, the kind of rumble the
road makes when a train passes is probably calling for a more severe duty
tubing than most road surfaces. The asphalt is grey, and older than 2 years,
if that is a help. Should I simply get a carbon frame to deal with this type
of use more effectively?
>In short: any frame can be a good frame built from any material. But
>it is an individual thing that has to do with geometry of the bike,
>the weightof the rider, the size of the tubing and the wheel and
>tire combination on the finished bike.
I thought you said that I specifcally wanted a 'stiff' frame for flying at
45 mph, have you changed your mind? Is it that they are simply ALL good, and
'stiff' ones are better?
>For instance, I have had several problems with my Colnago Super getting
>wobbles in fast downhills after hitting a Bot's Dot or some such.
I'd bet some suspension incorporated into that Colnago would cure that
problem right away. Maybe suspension could give 'stiffness' a run for its
money in making a better frame, d'ya think?
>I just had some problems with the wheels (American Classic hubs
>and Campi Aero rims) and changed to my Mavic hubbed, Araya super
>aero rims and the problem seems to have disappeared. The first
>set have 23 mm Continental GP's while the second have 28 mm Avosets
>(these are really only 25 mm).
Do you guess that the new wheels are more 'stiff' then?
>My Eddy Merckx with oversized tubing (61 cm size frames mind you)
>never has given a seconds scare. My Graftek carbon fiber, never.
>Stiff is better, if you need compliance you get it from the tires.
Wow, you sure do have quite the stable of bikes. I personally ride a
15 1/2" size frame, I guess my tubing is undersized then, right? I'd
really like to get onto one of those interior cubicle bicycle frames you
mention, given this new information, although I'm confused about how tires
make people describe aluminum frames as harsh when you've made it pretty
clear that whether the frame is made of steel, titanium, aluminum, or
whatever, it can be good, and it can be 'stiff.' No, actually I'm confused
to the third power.
-Brian
--
DEMPSEY,BRIAN DAVID
Georgia Institute of Technology, Atlanta Georgia, 30332
uucp: ...!{decvax,hplabs,ncar,purdue,rutgers}!gatech!prism!ch89abe
Internet: ch8...@prism.gatech.edu
William Kellagher
In article <NEWTNews.8709675...@pp000428.mindspring.com>, pp00...@mindspring.com writes:
>
>With Cont GPs inflated to 130-135psi (which makes for a pretty harsh
>riding tire) the ride characteristics of my old Centurion Ironman vs
>my Spectrum (Merlin) titanium frame are unmistakable. If this is
>not due to frame compliance, then what else am I supposed to
>attribute it to?
>
The fork, and the wheelbase of the respective frames.
Bill Kellagher
hau...@mbi.org
In article <NEWTNews.8709675...@pp000428.mindspring.com> pp00...@mindspring.com writes:
>From: pp00...@mindspring.com
>Subject: Re: Why do people think Alu frames are HARSHER? / One for Jobst ! / Tom K.
>Date: Thu, 07 Aug 97 08:05:37 PDT
>>
>> In article <tomkEEH...@netcom.com> to...@netcom.com (Thomas H.
>Kunich) writes:
>>
>> >In article
><NEWTNews.8708146...@pp000428.mindspring.com>,
>> > <pp00...@mindspring.com> wrote:
>>
>> >>Perhaps someone will profit from this information with which I
>am
>> >>already familiar. For the most part I am in agreement with you.
>I
>> >>too ride a 61cm frame on 23mm Conti GPs, but unlike yourself, I
>find
>> >>the compliance provided by my titanium frame to be welcome after
>> >>being beaten to death for years on a less compliant steel frame.
>>
>> >My, my. A bit touchy after spending all that money on a bicycle?
>>
>> >Now don't get me wrong. A titanium frame is nice. They will
>probably
>> >last forever, they won't rust, they look cool, etc.
>>
>> >But if you bought it for the ride you did the wrong thing. And if
>> >it rides well it's because everything came together properly
>> >and that is generally luck aided by a century of trying to find
>> >out what would work well.
>>
>> >So, how do you tell this "compliance" when the frame bends about
>> >10% as much as the tires do?
>>
>>
>> Thomas, Hell has apparently frozen over, because I am in total
>agreement with
>> you.
>>
>
>Rich,
>With Cont GPs inflated to 130-135psi (which makes for a pretty harsh
>riding tire) the ride characteristics of my old Centurion Ironman vs
>my Spectrum (Merlin) titanium frame are unmistakable.
I think you mean they're unmistakable different?
If this is
>not due to frame compliance, then what else am I supposed to
>attribute it to?
Of course they have different characteristics! Two steel frames, unless
identical, will have different characteristics. They have different length
tubes, different angles, different masses, and different stiffnesses (and
other variables I left out, no doubt).
Since titanium is a stepping stone between aluminum and steel, a bigger
difference in frames is noticed between a standard steel frame and an
oversized aluminum one. The aluminum will probably be stiffer, yet
lighter. This makes it more responsive, yet more comfortable (since comfort
is related to mass). Of course there are many other variables - probably the
most important of which is how well the frame fits the rider. A feeling of
'oneness' with the bike cannot be obtained if the frame doesn't fit.
The argument I (and Thomas, I think) was refuting was that aluminum frames
have a harsher ride. This neither means nor implies that there isn't a
noticeable difference in other ways. Certainly this will also be true of your
titanium frame, but the differences result from many things, not just that
it's made of titanium.
>There is little point in arguing over if the resulting package
>works, when in fact one ride convinces you that it does. To ride it
>is to love it. Enough said. - Jim McNamara
I agree! This is often the case with expensive bicycles. It's no coincidence
that expensive frames and components tend to be well designed.
Rich
Matt O'Toole
pp00...@mindspring.com wrote in article
<NEWTNews.8709709...@pp000428.mindspring.com>...
> As concerns frame
> complaince, perhaps the empirical scrutiny of the scientific method
> and its resulting tests and measurements fail to capture the
> perception a rider feels when riding a given bike (frame), but it is
> hard to ignore one's experience, even if such experience is one
> conjured up by one's own psyche. If what is at work here is some
> sort of placebo effect, I care not, as long as it seems to work.
By the same reasoning, Slick 50 works well in automotive engines, magnets
strapped to your pipes will soften the water coming into your home, and
neoprene girdles will melt the fat off your body. You're a salesman's
dream!
> I still have some difficulty believing that there isn't something to
> vertical frame compliance and its ability to impart some comfort,
> directly dependent upon choice of material, wall thickness, tubing
> diameter, butting, flaring, curvature, etc.
In Columbus' time, the world's leaders had difficulty believing the earth
was not flat. They also lacked scientific knowledge, and refused to see
things from anywhere but their own, limited and flawed perspective.
Matt O.
pp00...@mindspring.com
In Article<tomkEEH...@netcom.com>, <to...@netcom.com> writes:
> Newsgroups: rec.bicycles.tech
> Path:
interramp.com!psinntp!news.idt.net!netnews.com!ix.netcom.com!tomk
> From: to...@netcom.com (Thomas H. Kunich)
> Subject: Re: Why do people think Alu frames are HARSHER? / One for
Jobst ! / Tom K.
> Message-ID: <tomkEEH...@netcom.com>
> Organization: Netcom
> References: <33DE77...@uclink2.berkeley.eduREMOVE>
<NEWTNews.8707921...@pp000428.mindspring.com>
<tomkEEG...@netcom.com>
<NEWTNews.8708146...@pp000428.mindspring.com>
> Date: Wed, 6 Aug 1997 14:21:28 GMT
> Lines: 26
> Sender: to...@netcom17.netcom.com
>
> In article
<NEWTNews.8708146...@pp000428.mindspring.com>,
> <pp00...@mindspring.com> wrote:
>
> >Perhaps someone will profit from this information with which I am
> >already familiar. For the most part I am in agreement with you.
I
> >too ride a 61cm frame on 23mm Conti GPs, but unlike yourself, I
find
> >the compliance provided by my titanium frame to be welcome after
> >being beaten to death for years on a less compliant steel frame.
>
> My, my. A bit touchy after spending all that money on a bicycle?
>
> Try riding one og those 'less compliant' stiff steel frames with
> Jobst's favorite tires: Avocets, say 25 or 28 mm? Then tell us
> about how compliant the ride is on the ti bike.
>
> Now don't get me wrong. A titanium frame is nice. They will
probably
> last forever, they won't rust, they look cool, etc.
>
> But if you bought it for the ride you did the wrong thing. And if
> it rides well it's because everything came together properly
> and that is generally luck aided by a century of trying to find
> out what would work well.
>
> So, how do you tell this "compliance" when the frame bends about
> 10% as much as the tires do?
>
Tom,
Please see my latest response to Rich (hau...@mbi.org) in this
regard. I believe, in quoting you, he left out your suggestion
regarding Jobst's favorite tires (the Avocet 25-28mm). I've ridden
this tire and consider it to be a good one, although it is not my
tire of choice. I've ridden them on my old Centurion Ironman, but
still found the comfort level of this frame, with these tires, to
leave something to be desired. Granted, I have not ridden these
tires on my ti frame and probably never will. With the Conti price
increase, I am seriously considering changing over to Vittoria or
Hutchinson tires. Perhaps I'll have to post an inquiry to the
newsgroup soliciting opinions concerning the merits of each. That's
a bit off topic though. As to why I purchased the ti frame, it was
for various reasons ... ride, strength, durability, weight (lack
thereof), appearance, snob appeal among them. As concerns frame
complaince, perhaps the empirical scrutiny of the scientific method
and its resulting tests and measurements fail to capture the
perception a rider feels when riding a given bike (frame), but it is
hard to ignore one's experience, even if such experience is one
conjured up by one's own psyche. If what is at work here is some
sort of placebo effect, I care not, as long as it seems to work. I
still have some difficulty believing that there isn't something to
vertical frame compliance and its ability to impart some comfort,
directly dependent upon choice of material, wall thickness, tubing
diameter, butting, flaring, curvature, etc. This aside, this thread
has departed quite a bit from its original intent which addressed
itself to lateral compliance and wasted energy. but I guess that's
neither here nor there at this point. - Jim McNamara
Michael Higuchi
kell...@sweng.stortek.com (William Kellagher) wrote:
>In article <NEWTNews.8709675...@pp000428.mindspring.com>, pp00...@mindspring.com writes:
>>
>>With Cont GPs inflated to 130-135psi (which makes for a pretty harsh
>>riding tire) the ride characteristics of my old Centurion Ironman vs
>>my Spectrum (Merlin) titanium frame are unmistakable. If this is
>>not due to frame compliance, then what else am I supposed to
>>attribute it to?
>>
>
>
>The fork, and the wheelbase of the respective frames.
>
>
I'd add: saddle, and chainstay length.
- __o Michael Higuchi
- _-\<,_ mhig...@ibm.net
- (*)/ (*) Key ID: 0x4AECA14D
Key FP: 31 EE 11 32 B1 9D 85 59 23 A3 6D 70 09 8E 60 8D
John Connolly
Don Meredith wrote:
>
> Frame flex wasting energy isn't a myth. Remember that energy in equals
> work out. Given the same energy in, less frame flex allows for more
> work to go towards turning the cranks and spinning the wheel. I won't
> argue how large a percentage this is but it definitely takes energy to
> torque the frame around. Obviously the stiffness for transmission
> efficiency needs to be balanced with compliance that avoids vibration
> fatigue in the muscles.
>
> --
> Don Meredith
> Mechanical Engineering
> Clemson University
Don, I don't want to get into a technical argument over this, but some
thoughts...
If a rider is "torquing" the frame, the energy is RETURNED when the
frame "unwraps". The only difference is the timed release of this
energy, as opposed to instantaneous power transmission. In other words,
the energy is released when the torque is backed down a bit.
Secondly, any energy wasted by the rider "torquing" the frame, is going
to be wasted if he is riding a STIFF frame. The torque is still present,
it is just the frame is not deflecting. The rider is basically fighting
himself/herself, or to accelerate/maintain/climb to get the torque.
Frame flex doesn't come into it (in my opinion).
You can view the frame flex as an electrical equivalent of a capacitor,
or a mechanical equevalent of a spring (or holding tank for pressure).
Sure there is energy loss with the "winding and unwinding", but it is
ridiculous to assume this is significant enough to worry about.
The only thing the flex changes is WHEN the energy is released. It
doesn't dissappear.
Vibration is another story, which I am not going to go into, I have made
comments on that subject before.
John
Tom Ace
John Connolly wrote:
> The only thing the flex changes is WHEN the energy is released. It
> doesn't dissappear.
Assume the rider pours on the coal when the crank is at 2-3 o'clock
and flexes the frame at that moment. The rider then lets up when
the crank is at the bottom (6 o'clock) and the frame springs back.
Downward force on the crank at that point in the stroke doesn't
propel the bicycle, and most of the energy returned by the frame
may be dissipated (wasted as heat) in the rider's leg.
I am not claiming this represents a substantial waste of energy
with most frames; my point is only that even if the frame is
perfectly elastic, there's no guarantee that the energy it stores
when flexing is later directed toward propelling the bicycle.
Tom Ace
cr...@best.com
hau...@mbi.org
In article <33EACE48...@best.comX> Tom Ace <cr...@best.comX> writes:
>From: Tom Ace <cr...@best.comX>
>Subject: Re: Why do people think Alu frames are HARSHER? / One for Jobst ! / Tom K.
Exactly. John also seems to assume that the frame flexes in only one way, and
that when it flexes back, it results in 100% of that energy propelling the
bike. Actually the tubes flex in two dimensions.
Moreover, as the tubes flex, heat is generated. This energy is forever gone.
Rich
Rinards
In article <33EA72...@fix.net>, Ed Chait <ech...@fix.net> writes:
>Ok, so frame compliance is not what riders *feel* when riding frames
>built of different materials. It has been suggested that these
>different materials have different resonant frequencies and may transmit
>these frequencies to the rider.
A frame's resonant frequency is tranferred to the rider when the bike
wobbles or shimmies at speed. This is different from ride harshness.
Kestrel's brochure used to have a chart showing various frame materials'
damping abilities. Aluminum is worst, titanium is in the middle, steel
is better. All these metals overlapped for about 60% of the range shown.
Then they showed composites: they were ten times better than
roughly any of the metals.
I don't know how significant this is.
Damon Rinard
Rinards
In article <NEWTNews.8709709...@pp000428.mindspring.com>,
pp00...@mindspring.com writes:
>As concerns frame
>complaince, perhaps the empirical scrutiny of the scientific method
>and its resulting tests and measurements fail to capture the
>perception a rider feels when riding a given bike (frame)
Careful measurements have shown that diamond frames of all materials
are not significantly compliant in the vertical plane. See Bob Bundy's
excellent article in the FAQ.
You said "...when riding a given bike (frame)..."
A frame is not a bike, and a bike is not a frame. Unfortunately, in order
to ride a frame, it must be assembled into a bike. Have you ridden
your Centurian with the same equipment your Spectrum has? Are they
the same geometry? Both these differences have a far greater effect on
a bike's feel than the frame material.
> , but it is
>hard to ignore one's experience, even if such experience is one
>conjured up by one's own psyche. If what is at work here is some
>sort of placebo effect, I care not, as long as it seems to work. I
I agree that the effects of psyching up can provides results that are
nearly as real as measureable physical differences. Good track racers
often use psyching up (and psyching out their opponents) to great
success.
But this is rec.bicycles.tech, not rec.bicycles.psych. If frame
harshness or vertical compliance is a placebo, we wish to discover it.
>I still have some difficulty believing that there isn't something to
>vertical frame compliance and its ability to impart some comfort,
>directly dependent upon choice of material, wall thickness, tubing
>diameter, butting, flaring, curvature, etc.
Stop having difficulty believing. Vertical frame compliance in
diamond frames is insignificant. Believing this is easy if you
read Bob Bundy's article "frame stiffness" in the FAQ.
>This aside, this thread
>has departed quite a bit from its original intent which addressed
>itself to lateral compliance and wasted energy.
The subject line says "harsher", not "energy wasted due to lateral frame
flex".
Best Wishes,
Damon Rinard
THolland63
Jim McNamara asked about the sweet ride of his Ti frame:
> supposed to attribute it to?
To which Bill Kellagher replied:
> The fork, and the wheelbase of the respective frames.
and Michael Higuchi wrote:
> I'd add: saddle, and chainstay length.
Gentlemen:
Two years ago, I switched my components off my trusty Klein Quantum to a
Merlin. It rides smoother and it handles better, especially on rough
pavement. These observations were made using the same size frames, the
*same* fork (Kinesis), saddle, and tires. Oh, and the Klein has more
wheelbase, with its longer top tube and "unfashionably" long chainstays.
Not that the Klein didn't handle like a champ, it did, but the Merlin is
better. Especially noticeable is how the rear wheel doesn't lift and skip
so easily in a sprint.
T. Holland
Todd Holland
THoll...@spam.org ;)
to e-mail, use @aol.com
Rick Denney
Rinards wrote:
...
>
> Stop having difficulty believing. Vertical frame compliance in
> diamond frames is insignificant. Believing this is easy if you
> read Bob Bundy's article "frame stiffness" in the FAQ.
>
I note with some amusement that when Cannondale built bikes for the
Saeco team, they abandoned their own frame design and started with the
geometry of laste year's Mosers (steel). The riders felt fine on the
Cannondales. What makes Cannondales harsh isn't the material, it seems
from that story, it is the tight criterium geometry. Using European road
racing geometry--the aluminum bike felt like any other classic road
bike, according to the author of the article on the subject in the
latest Bicyclist.
My Eddy Merckx MX-Leader is monstrously stiff. But it is also one of the
most comfortable bikes I've ever ridden. That fact forced me to
reconsider all I've ever believed about frame materials. The feel IS
different, but not as different as we've always thought, and not for the
reasons we've always thought.
Joe Lucchio
Matt O'Toole wrote:
>
> Joe Lucchio <eco...@sparc1.castles.com> wrote in article
> <33E8DE...@sparc1.castles.com>...
>
> > So what your saying is that winning races is strickly based upon the
> > persons physical makeup and that there is no such thing as a
> > psychological edge? My point being is that perception, while it is not
> > backed up by empirical data, probably has more of an influence on how a
> > person relates to certain things such as bicycles and their ride
> > qualities. If it were up to engineers, perception wouldn't exist.
>
> If there were no perception, engineering wouldn't exist. Engineering is
> based on correct perception. Engineers understand the limits of human
> perception. Thus, they use reliable and precise tools and instruments to
> make their measurements, and improve their perception, rather than relying
> on flawed human perception.
>
> Advertising and marketing, on the other hand, are often based on myth and
> misperception. The art of illusion is employed to make the customer see
> and feel things that aren't there. If you need such illusion to get
> through life, fine, there are plenty of slimy salesmen out there ready to
> take your money.
>
> Matt O.
>
How could something be a "correct" perception. By nature, perception is
subjective. Furthermore, if engineers are human, which is questionable,
then their perceptions are human and by your definition, flawed.
Matt O'Toole
Ed Chait <ech...@fix.net> wrote in article <33EA72...@fix.net>...
> Ok, so frame compliance is not what riders *feel* when riding frames
> built of different materials. It has been suggested that these
> different materials have different resonant frequencies and may transmit
> these frequencies to the rider.
It has been suggested, and also rebutted. Did you read all the way through
Bob Bundy's article from the FAQ? To summarize, the frequencies you refer
to wouldn't be transmitted by the tires or saddle.
> If these frequencies are perceived as different ride qualities from one
> material to another, what's wrong with bicyclists and magazine editors
> commenting on the ride quality of one bike vs another?
>
> Of course, if they attribute it to the frames stiffness or lack thereof,
> they would be mistaken,
That's the whole point. They're passing on misinformation, and that's
wrong.
> but they are still perceiving a difference
> between bikes
So, identify what that difference is and report it, instead of freely
redistributing old wives' tales.
> and it seems as if these comments are universal enough to
> have some credence.
In some countries, the universal belief is that the earth is carried on the
back of a giant turtle. Does the universality of this belief give it
credence?
Matt O.
Ed Chait
Rinards wrote:
>
>
> A frame's resonant frequency is tranferred to the rider when the bike
> wobbles or shimmies at speed. This is different from ride harshness.
Thanks for the correction. I though I was using the correct terminology
to try to describe what I was thinking. I understand what you're
saying.
>
> Kestrel's brochure used to have a chart showing various frame materials'
> damping abilities. Aluminum is worst, titanium is in the middle, steel
> is better. All these metals overlapped for about 60% of the range shown.
>
> Then they showed composites: they were ten times better than
> roughly any of the metals.
>
> I don't know how significant this is.
>
I have a friend where I work who owns a Kestrel, and we're about the
same size. Maybe if I leave my firstborn with him, he'll let me ride
it.
Nah, bad exchange:).
Ed Chait
Ed Chait
Matt O'Toole wrote:
> So, identify what that difference is and report it, instead of freely
> redistributing old wives' tales.
I have to qualify, or rather dis-qualify my comments by saying that I am
just a recreational rider with no engineering background. I probably
should not be participating in this discussion, but it reminds me so
much of many of the high end audio debates that I've witnessed, that the
issue intrigues me. Audiophiles argue endlessly about the "qualities
and characteristics" of components and sound, some using sophisticated
instruments to "prove" their points. Unfortunately, none of these
instruments is as sophisticated as the human ear. There is little
common ground between the objectivists and subjectivists, and I tend to
dismiss either extreme.
I certainly did not intend to perpetuate any old wives' tale, so I
apologize for making a suggestion which has been completely ruled out
scientifically.
>
> In some countries, the universal belief is that the earth is carried on the
> back of a giant turtle. Does the universality of this belief give it
> credence?
>
Only if the turtle is made out of titanium.
Ed Chait
Mark Atanovich
In article <NEWTNews.8709709...@pp000428.mindspring.com>
pp00...@mindspring.com writes:
>
> Please see my latest response to Rich (hau...@mbi.org) in this
> regard. I believe, in quoting you, he left out your suggestion
> regarding Jobst's favorite tires (the Avocet 25-28mm). I've ridden
> this tire and consider it to be a good one, although it is not my
> tire of choice. I've ridden them on my old Centurion Ironman, but
> still found the comfort level of this frame, with these tires, to
> leave something to be desired. Granted, I have not ridden these
> tires on my ti frame and probably never will. With the Conti price
> increase, I am seriously considering changing over to Vittoria or
> Hutchinson tires. Perhaps I'll have to post an inquiry to the
> newsgroup soliciting opinions concerning the merits of each. That's
> a bit off topic though. As to why I purchased the ti frame, it was
> for various reasons ... ride, strength, durability, weight (lack
> thereof), appearance, snob appeal among them. As concerns frame
> complaince, perhaps the empirical scrutiny of the scientific method
> and its resulting tests and measurements fail to capture the
> perception a rider feels when riding a given bike (frame), but it is
> hard to ignore one's experience, even if such experience is one
> conjured up by one's own psyche. If what is at work here is some
> sort of placebo effect, I care not, as long as it seems to work. I
> still have some difficulty believing that there isn't something to
> vertical frame compliance and its ability to impart some comfort,
> directly dependent upon choice of material, wall thickness, tubing
> diameter, butting, flaring, curvature, etc. This aside, this thread
> has departed quite a bit from its original intent which addressed
> itself to lateral compliance and wasted energy. but I guess that's
> neither here nor there at this point. - Jim McNamara
>
What about the freakin' saddle?
Mark_Atano...@fcc.gov
To reply, replace fcc.gov w/ email.sps.mot.com
Pjwig
Let's not forget the factor of the weight of the rider when judging how
harshly a frame rides. I bought my '89 Cannondale SR900 off a guy who
only weighed 130 lbs. He claimed the frame wasn't any good because he had
his fillings rattled out. I, OTOH, weigh 180 (when at "fighting weight") &
found the 'dale to ride quite nicely, actually better than, IMHO, the
Bianchi Competezione (SLX) & Masi Nuova Strada (SL) I had previously
owned. It appears to me that the fatter tubed aluminum bikes ride better
when more heavily loaded. Thinner tubed aluminum frames such as Vitus &
Alan seem to better serve riders under 165 lbs. I've known a few heavier
riders complain about those being springy & flexing too much.
Just my 2 cents on the matter.
Mark Atanovich
In article <19970811140...@ladder02.news.aol.com>
pj...@aol.com (Pjwig) writes:
> Let's not forget the factor of the weight of the rider when judging how
> harshly a frame rides.
Yes, for reasons other than the frame. Heavier riders compress the
saddle more and unless higher tire pressures are used, they will
provide more compliance.
> I bought my '89 Cannondale SR900 off a guy who
> only weighed 130 lbs. He claimed the frame wasn't any good because he had
> his fillings rattled out. I, OTOH, weigh 180 (when at "fighting weight") &
> found the 'dale to ride quite nicely, actually better than, IMHO, the
> Bianchi Competezione (SLX) & Masi Nuova Strada (SL) I had previously
> owned. It appears to me that the fatter tubed aluminum bikes ride better
> when more heavily loaded. Thinner tubed aluminum frames such as Vitus &
> Alan seem to better serve riders under 165 lbs. I've known a few heavier
> riders complain about those being springy & flexing too much.
> Just my 2 cents on the matter.
Laterally, though.
pp00...@mindspring.com
In Article<33EACE48...@best.comX>, <cr...@best.comX> writes:
> Path: interramp.com!psinntp!news.idt.net!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!howland.erols.net!newshub2.home.com!newshub1.home.com!news.home.com!news1.best.com!nntp2.ba.best.com!not-for-mail
> From: Tom Ace <cr...@best.comX>
> Newsgroups: rec.bicycles.tech
> Subject: Re: Why do people think Alu frames are HARSHER? / One for Jobst ! / Tom K.
> Date: Fri, 08 Aug 1997 00:44:08 -0700
> Lines: 19
> Message-ID: <33EACE48...@best.comX>
> References: <33DE77...@uclink2.berkeley.eduREMOVE> <5rq8na$1k...@itssrv1.ucsf.edu> <5s4rr6$9...@dfw-ixnews7.ix.netcom.com> <NEWTNews.8707921...@pp000428.mindspring.com> <tomkEEG...@netcom.com> <NEWTNews.8708146...@pp000428.mindspring.com> <drmered.870839407@hub
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>
> John Connolly wrote:
>
> > The only thing the flex changes is WHEN the energy is released. It
> > doesn't dissappear.
>
> Assume the rider pours on the coal when the crank is at 2-3 o'clock
> and flexes the frame at that moment. The rider then lets up when
> the crank is at the bottom (6 o'clock) and the frame springs back.
> Downward force on the crank at that point in the stroke doesn't
> propel the bicycle, and most of the energy returned by the frame
> may be dissipated (wasted as heat) in the rider's leg.
>
> I am not claiming this represents a substantial waste of energy
> with most frames; my point is only that even if the frame is
> perfectly elastic, there's no guarantee that the energy it stores
> when flexing is later directed toward propelling the bicycle.
>
> Tom Ace
> cr...@best.com
Tom,
At last we are getting the the crux of the matter here. It will be
interesting to see haow thigs develop now that the cards have been
laid on the table. - Jim McNamara
pp00...@mindspring.com
In Article<19970808143...@ladder01.news.aol.com>, <rin...@aol.com> writes:
> Path: interramp.com!psinntp!howland.erols.net!infeed1.internetmci.com!newsfeed.internetmci.com!portc03.blue.aol.com!newstf02.news.aol.com!audrey01.news.aol.com!not-for-mail
> From: rin...@aol.com (Rinards)
> Newsgroups: rec.bicycles.tech
> Subject: Re: Why do people think Alu frames are HARSHER? / One for Jobst ! / Tom K.
> Date: 8 Aug 1997 14:32:38 GMT
> Lines: 53
> Message-ID: <19970808143...@ladder01.news.aol.com>
> NNTP-Posting-Host: ladder01.news.aol.com
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> References: <NEWTNews.8709709...@pp000428.mindspring.com>
> Organization: AOL http://www.aol.com
> X-Newsreader: AOL Offline Reader
>
> In article <NEWTNews.8709709...@pp000428.mindspring.com>,
> pp00...@mindspring.com writes:
>
> >As concerns frame
> >complaince, perhaps the empirical scrutiny of the scientific method
> >and its resulting tests and measurements fail to capture the
> >perception a rider feels when riding a given bike (frame)
>
> Careful measurements have shown that diamond frames of all materials
> are not significantly compliant in the vertical plane. See Bob Bundy's
> excellent article in the FAQ.
>
> You said "...when riding a given bike (frame)..."
>
> A frame is not a bike, and a bike is not a frame. Unfortunately, in order
>
> to ride a frame, it must be assembled into a bike. Have you ridden
> your Centurian with the same equipment your Spectrum has? Are they
> the same geometry? Both these differences have a far greater effect on
> a bike's feel than the frame material.
>
> > , but it is
> >hard to ignore one's experience, even if such experience is one
> >conjured up by one's own psyche. If what is at work here is some
> >sort of placebo effect, I care not, as long as it seems to work. I
>
> I agree that the effects of psyching up can provides results that are
> nearly as real as measureable physical differences. Good track racers
> often use psyching up (and psyching out their opponents) to great
> success.
>
> But this is rec.bicycles.tech, not rec.bicycles.psych. If frame
> harshness or vertical compliance is a placebo, we wish to discover it.
>
> >I still have some difficulty believing that there isn't something to
> >vertical frame compliance and its ability to impart some comfort,
> >directly dependent upon choice of material, wall thickness, tubing
> >diameter, butting, flaring, curvature, etc.
>
> Stop having difficulty believing. Vertical frame compliance in
> diamond frames is insignificant. Believing this is easy if you
> read Bob Bundy's article "frame stiffness" in the FAQ.
>
> >This aside, this thread
> >has departed quite a bit from its original intent which addressed
> >itself to lateral compliance and wasted energy.
>
> The subject line says "harsher", not "energy wasted due to lateral
frame
> flex".
>
> Best Wishes,
>
> Damon Rinard
I'll have to review the FAQ. - I certainly know the difference
between a frame and a bicycle and yes I have ridden both varieties
with the same components, however, the frame geometries are close,
though not exactly the same, so it is a bit like comparing apples
and oranges. - Jim McNamara
Matt O'Toole
pp00...@mindspring.com wrote in article
<NEWTNews.8713183...@pp000428.mindspring.com>...
> If you were to speak to those who know me well, you would soon learn
> that I am anything but, as you put it, "a salesman's dream". Ok,
> I'll agree with you about the neoprene girdle. As far a slick 50 is
> concerned, there are those who swear by the stuff, but I haven't
> read the body of supporting evidence or had any first hand
> experience with the product, so I'll refrain form comment. Now
> regarding those magnets, until you puruse the related studies and
> evidence, I wouldn't be too cynical. Certainly there is snake oil
> and charlatans in every field of endeavor, but before being too
> critical, I'd suggest you do a bit more research in this particular
> arena. - Jim Mc Namara
Which arena do you refer to, magnets or bicycles? If it's bicycles you're
talking about, there's a pretty good article in the FAQ on frame deflection
and "road feel". It's been posted in the course of this thread. Did you
bother to read it? If you wish to continue real discussion on this
subject, the points made in that article are always up for question and
comment. You could quote and take issue with any of those points. If you
have anything new to offer, we're all ears.
Matt O.
da...@erinet.com
>>> The only thing the flex changes is WHEN the energy is released. It
>>> doesn't dissappear.
>
>>Assume the rider pours on the coal when the crank is at 2-3 o'clock
>>propel the bicycle, and most of the energy returned by the frame
>>may be dissipated (wasted as heat) in the rider's leg.
>
>>I am not claiming this represents a substantial waste of energy
>>with most frames; my point is only that even if the frame is
>>perfectly elastic, there's no guarantee that the energy it stores
>>when flexing is later directed toward propelling the bicycle.
>
>that when it flexes back, it results in 100% of that energy propelling the
>bike. Actually the tubes flex in two dimensions.
>
>Moreover, as the tubes flex, heat is generated. This energy is forever gone.
There's a fairly well done article on this in the FAQ. Based on frame
flexing experiments and measurements therefrom with frames built from
various materials, frame flex is almost irrelevant. Unless someone has
some real data about the energy stored or energy lost or energy
returned, it would seem most likely that the "energy" part of this
matter is about like the frame rigidity -- namely, irrelevant.
.............dh
pp00...@mindspring.com
In Article<33EA72...@fix.net>, <ech...@fix.net> writes:
> Path: interramp.com!psinntp!news.idt.net!cam-news-hub1.bbnplanet.com!cpk-news-hub1.bbnplanet.com!news.bbnplanet.com!howland.erols.net!nntp1.crl.com!zinger.callamer.com!not-for-mail
> From: Ed Chait <ech...@fix.net>
> Newsgroups: rec.bicycles.tech
> Subject: Re: Why do people think Alu frames are HARSHER? / One for Jobst ! / Tom K.
> Date: Thu, 07 Aug 1997 18:12:52 -0700
> Organization: Call America Internet Services +1 (800) 563-3271
> Lines: 26
> Message-ID: <33EA72...@fix.net>
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>
> Matt O'Toole wrote:
> >
> ]
> > In Columbus' time, the world's leaders had difficulty believing
the earth
> > was not flat. They also lacked scientific knowledge, and
refused to see
> > things from anywhere but their own, limited and flawed
perspective.
> >
> > Matt O.
>
>
> Ok, so frame compliance is not what riders *feel* when riding
frames
> built of different materials. It has been suggested that these
> different materials have different resonant frequencies and may
transmit
> these frequencies to the rider.
>
> If these frequencies are perceived as different ride qualities
from one
> material to another, what's wrong with bicyclists and magazine
editors
> commenting on the ride quality of one bike vs another?
>
> Of course, if they attribute it to the frames stiffness or lack
thereof,
> they would be mistaken, but they are still perceiving a difference
> between bikes and it seems as if these comments are universal
enough to
> have some credence.
>
>
> Ed Chait
Ed,
Well said Ed ... and I'm a poet and don't know it. As the poster
who started all this, I'd like to say that I concur with your
observation. - What I neglected to say in all my previous posts,
however, is that my titanium frame, feels not altogether different
than those constructed of some other material when ridden over
really bad surfaces like railroad crossings, but over less forgiving
road imperfections such as dips, its really more comfortable than my
old steel variety. That having been said, I wanted to add that I
agree that perceptual differences between bikes would seem to be
common enough to warrant some degree of credability to what is
generally perceived as "feel". - Jim McNamara
pp00...@mindspring.com
In Article<33EAC3...@sisna.comREMOVE_TO_E-MAIL>, <con...@sisna.comREMOVE_TO_E-MAIL> writes:
> Message-ID: <33EAC3...@sisna.comREMOVE_TO_E-MAIL>
> Date: Fri, 08 Aug 1997 00:58:14 -0600
> From: John Connolly <con...@sisna.comREMOVE_TO_E-MAIL>
> X-Mailer: Mozilla 3.01Gold (Win95; I)
> MIME-Version: 1.0
> Newsgroups: rec.bicycles.tech
> Subject: Re: Why do people think Alu frames are HARSHER? / One for Jobst ! / Tom K.
> References: <33DE77...@uclink2.berkeley.eduREMOVE> <5rq8na$1k...@itssrv1.ucsf.edu> <5s4rr6$9...@dfw-ixnews7.ix.netcom.com> <NEWTNews.8707921...@pp000428.mindspring.com> <tomkEEG...@netcom.com> <NEWTNews.8708146...@pp000428.mindspring.com> <drmered.870839407@hub
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> The only thing the flex changes is WHEN the energy is released. It
> doesn't dissappear.
>
> Vibration is another story, which I am not going to go into, I
have made
> comments on that subject before.
>
>
> John
John,
Thanks for your contribution to this thread. Things are really
starting to heat up. This is precisely the direction I expected
this thread to eventually take. It's just about time for Jobst to
jump in. - Jim McNamara
Thomas H. Kunich
>It has been suggested that these
>different materials have different resonant frequencies and may transmit
>these frequencies to the rider.
>
>If these frequencies are perceived as different ride qualities from one
>material to another, what's wrong with bicyclists and magazine editors
>commenting on the ride quality of one bike vs another?
Because the "ringing" of the frame isn't a "ride quality" any more
than the wind noise outside of your car window is a driving quality.
All it means is that if you were blind-folded and rode several bikes
made of different material, you'd be able to tell one from the other.
Being able to tell the difference is misconstrued by the uneducated
as having different "quality" or ride. Preposterous!
Steel has a characteristic "ring" when ridden. Aluminum, titanium and
carbon fiber all are missing this characteristic. That has nothing whatsoever
to do with what frame material is best. Any material can made quality
frames.
Thomas H. Kunich
In article <NEWTNews.8709675...@pp000428.mindspring.com>,
<pp00...@mindspring.com> wrote:
>With Cont GPs inflated to 130-135psi (which makes for a pretty harsh
>riding tire) the ride characteristics of my old Centurion Ironman vs
>my Spectrum (Merlin) titanium frame are unmistakable. If this is
>not due to frame compliance, then what else am I supposed to
>attribute it to? As far as "touchy after spending all that money"
>is concerned, I'm neither touchy nor concerned with the money which
>I feel was well spent. The current value of the bike is in excess
>of $5000 with current components and worth every penny. I could
>have just as easily blown the money at a crap table, with nothing to
>show for it. My selection of parts produced a bicycle suitable for
>my particular purposes. Call it luck, if you may, but all the parts
>came together properly without a century of trial and error effort.
>There is little point in arguing over if the resulting package
>works, when in fact one ride convinces you that it does. To ride it
>is to love it. Enough said. - Jim McNamara
>
Uh, maybe if you put the two bikes next to each other and measure
the differences you will begin to see why they fell different. In
any case, comparing a perfect, expensive, well thought out bike like
the Merlin with a mass produced upper-middle class bike like the
Centurion isn't a very fair comparison don't you think?
Why not compare your Merlin with a Master Light?
Thomas H. Kunich
In article <haubert.62...@mbi.org>, <hau...@mbi.org> wrote:
>Actually aluminum is about 1/3 the stiffness, 1/3 the weight, and 1/3 the
>strength of steel. I don't think that's any secret. What doesn't seem to be
>well-understood, though, is that titanium is about 60% the weight and
>stiffness of steel. Thus, replacing aluminum with titanium adds weight - it
>doesn't subtract it. This feeling that titanium is somehow stronger than
>steel, yet lighter than aluminum still seems to exist. I suspect that people
>attempt to justify the price by attributing magical qualities to it. In
>reality, though, titanium is simply a stepping stone between the two less
>costly metals; thus, a titanium frame should be slightly oversized, as
>compared to a traditional steel frame.
Psst, Rich: because of aluminum's fatique characteristics you need to
use about twice as much of it as would be indicated in simple
comparison's like you just made. Therefore aluminum frames, in order
to be as strong and reliable as steel frames are bout 60% of the weight.
Since titanium has good fatique characteristics you don't need the
additional safety margin.
So, titanium and aluminum bike should weight about the same all things
considered.
Carbon fiber should be used to construct the lightest frames, but there
are quality problems in the construction of any composite material
that make it smart to include large safety margins in frame construction
from that material too.
I don't know what is happening with Felt, but am curious what their
failure rate is. I notice that they aren't advertising with any
vigor but that may not mean anything these days. A friend has
a Felt that he raves about. But the frame weight gives me the willies
and I would be inspecting the downtube at the head tube before and
during every ride after the first year.
Thomas H. Kunich
In article <33EAC3...@sisna.comREMOVE_TO_E-MAIL>,
John Connolly <con...@sisna.comREMOVE_TO_E-MAIL> wrote:
>If a rider is "torquing" the frame, the energy is RETURNED when the
>frame "unwraps". The only difference is the timed release of this
>energy, as opposed to instantaneous power transmission. In other words,
>the energy is released when the torque is backed down a bit.
Consider: you are climbing a steep hill. You pull up on the off-side
pedal and the bike, instead of puting that energy into the rear
wheel, twists the bottom bracket to one side. As you release your
force near top dead center it moves your legs back instead of pushing
the bike forward. That is all lost energy.
THolland63
Tom K. writes:
>Steel has a characteristic "ring" when ridden. Aluminum,
When riding on rough roads, the handle of my Zefal HP can sometimes
vibrate against the top tube. Rrrring! If it's not wrapped with a rubber
band, the frame sounds like a telephone. It's titanium.
T. Holland
pp00...@mindspring.com
In Article<hauberk.65...@mba.orgy>, <hau...@mba.orgy>
writes:
> Path: inter ramp.com!psinntprincipalnhow
land.net!portc02.blue.aol.com!newserodespitt.edu!dsinc!nntablepenn.ne
was fee du!!mbi.org!haubert
> From: hau...@mbi.org
> Newsgroups: rec.bicycles.tech
> Subject: Re: Why do people think Alu frames are HARSHER? / One for
Jobst ! / Tom K.
> Date: Thu, 7 Aug 1997 15:32:54 UNDEFINED
> Organization: Michigan Biotechnology Institute
> Lines: 84
> Message-ID: <haubert.65...@mbi.org>
> References: <33DE77...@uclink2.berkeley.eduREMOVE>
<NEWTNews.8707921...@pp000428.mindspring.com>
<tomkEEG...@netcom.com>
<NEWTNews.8708146...@pp000428.mindspring.com>
<tomkEEH...@netcom.com> <haubert.654.001D3C9A@m
> NNTP-Posting-Host: bananna.mbi.org
> X-Newsreader: Trumpet for Windows [Version 1.0 Rev B]
>
> In article
<NEWTNews.8709675...@pp000428.mindspring.com>
pp00...@mindspring.com writes:
> >From: pp00...@mindspring.com
> >Subject: Re: Why do people think Alu frames are HARSHER? / One
for Jobst ! / Tom K.
> >Date: Thu, 07 Aug 97 08:05:37 PDT
>
>
> >>
> >> In article <tomkEEH...@netcom.com> to...@netcom.com (Thomas
H.
> >Kunich) writes:
> >>
> >> >In article
> ><NEWTNews.8708146...@pp000428.mindspring.com>,
> >> > <pp00...@mindspring.com> wrote:
> >>
> >> >>Perhaps someone will profit from this information with which
I
> >am
> >> >>already familiar. For the most part I am in agreement with
you.
> >I
> >> >>too ride a 61cm frame on 23mm Conti GPs, but unlike yourself,
I
> >find
> >> >>the compliance provided by my titanium frame to be welcome
after
>
> >> >>being beaten to death for years on a less compliant steel
frame.
> >>
> >> >My, my. A bit touchy after spending all that money on a
bicycle?
> >>
> >> >Now don't get me wrong. A titanium frame is nice. They will
> >probably
> >> >last forever, they won't rust, they look cool, etc.
> >>
> >> >But if you bought it for the ride you did the wrong thing. And
if
> >> >it rides well it's because everything came together properly
> >> >and that is generally luck aided by a century of trying to
find
> >> >out what would work well.
> >>
> >> >So, how do you tell this "compliance" when the frame bends
about
> >> >10% as much as the tires do?
> >>
> >>
> >> Thomas, Hell has apparently frozen over, because I am in total
> >agreement with
> >> you.
> >>
> >
> >Rich,
>
> >With Cont GPs inflated to 130-135psi (which makes for a pretty
harsh
> >riding tire) the ride characteristics of my old Centurion Ironman
vs
> >my Spectrum (Merlin) titanium frame are unmistakable.
>
> I think you mean they're unmistakable different?
>
> If this is
> >not due to frame compliance, then what else am I supposed to
> >attribute it to?
>
> Of course they have different characteristics! Two steel frames,
unless
> identical, will have different characteristics. They have
different length
> tubes, different angles, different masses, and different
stiffnesses (and
> other variables I left out, no doubt).
>
> Since titanium is a stepping stone between aluminum and steel, a
bigger
> difference in frames is noticed between a standard steel frame and
an
> oversized aluminum one. The aluminum will probably be stiffer,
yet
> lighter. This makes it more responsive, yet more comfortable
(since comfort
> is related to mass). Of course there are many other variables -
probably the
> most important of which is how well the frame fits the rider. A
feeling of
> 'oneness' with the bike cannot be obtained if the frame doesn't
fit.
>
> The argument I (and Thomas, I think) was refuting was that
aluminum frames
> have a harsher ride. This neither means nor implies that there
isn't a
> noticeable difference in other ways. Certainly this will also be
true of your
> titanium frame, but the differences result from many things, not
just that
> it's made of titanium.
>
> >There is little point in arguing over if the resulting package
> >works, when in fact one ride convinces you that it does. To ride
it
> >is to love it. Enough said. - Jim McNamara
>
> I agree! This is often the case with expensive bicycles. It's no
coincidence
> that expensive frames and components tend to be well designed.
>
> Rich
>
Rich,
Like I said in another post, there is much more to comfort than the
choice of frame material ... tubing diameter, wall thickness,
geometry, etc,. just to name a few. As aluminum goes, I think it
got its harsh ride reputation from those who have ridden the stiffer
Cannondale and Klein bikes. Had they ever ridden one of the older
Vitus frames, they would have discovered an entirely different
animal. - Jim McNamara
pp00...@mindspring.com
In Article<01bca364$b44c7d20$f0ca...@Pmatt.deltanet.com>,
<ma...@deltanet.com> writes:
> Path:
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t-for-mail
> From: "Matt O'Toole" <ma...@deltanet.com>
> Newsgroups: rec.bicycles.tech
> Subject: Re: Why do people think Alu frames are HARSHER? / One for
Jobst ! / Tom K.
> Date: 7 Aug 1997 19:03:23 GMT
> Organization: Delta Internet Services, Inc.
> Lines: 30
> Message-ID: <01bca364$b44c7d20$f0ca...@Pmatt.deltanet.com>
> References: <33DE77...@uclink2.berkeley.eduREMOVE>
<NEWTNews.8707921...@pp000428.mindspring.com>
<tomkEEG...@netcom.com>
<NEWTNews.8708146...@pp000428.mindspring.com>
<tomkEEH...@netcom.com>
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> NNTP-Posting-Host: anx-lkf1240.deltanet.com
> X-Newsreader: Microsoft Internet News 4.70.1161
>
>
>
> pp00...@mindspring.com wrote in article
> <NEWTNews.8709709...@pp000428.mindspring.com>...
>
> > As concerns frame
> > compliance, perhaps the empirical scrutiny of the scientific
method
> > and its resulting tests and measurements fail to capture the
> > perception a rider feels when riding a given bike (frame), but
it is
> > hard to ignore one's experience, even if such experience is one
> > conjured up by one's own psyche. If what is at work here is
some
> > sort of placebo effect, I care not, as long as it seems to work.
>
> By the same reasoning, Slick 50 works well in automotive engines,
magnets
> strapped to your pipes will soften the water coming into your
home, and
> neoprene girdles will melt the fat off your body. You're a
salesman's
> dream!
>
> > I still have some difficulty believing that there isn't
something to
> > vertical frame compliance and its ability to impart some
comfort,
> > directly dependent upon choice of material, wall thickness,
tubing
> > diameter, butting, flaring, curvature, etc.
>
> In Columbus' time, the world's leaders had difficulty believing
the earth
> was not flat. They also lacked scientific knowledge, and refused
to see
> things from anywhere but their own, limited and flawed
perspective.
>
> Matt O.
>
>
Ed Chait
Thomas H. Kunich wrote:
>
> In article <33EA72...@fix.net>, Ed Chait <ech...@fix.net> wrote:
>
> >It has been suggested that these
> >different materials have different resonant frequencies and may transmit
> >these frequencies to the rider.
> >
> >If these frequencies are perceived as different ride qualities from one
> >material to another, what's wrong with bicyclists and magazine editors
> >commenting on the ride quality of one bike vs another?
>
> Because the "ringing" of the frame isn't a "ride quality" any more
> than the wind noise outside of your car window is a driving quality.
> All it means is that if you were blind-folded and rode several bikes
> made of different material, you'd be able to tell one from the other.
>
> Being able to tell the difference is misconstrued by the uneducated
> as having different "quality" or ride. Preposterous!
>
> to do with what frame material is best. Any material can made quality
> frames.
When I mentioned "frequencies", I wasn't referring to anything auditory,
but rather to vibration. High frequency vibration, for instance, is
something that lots of people find very annoying and harsh, including
me. Is it not possible that these different frame materials transmit
the road surface in different ways to the rider?
Ed Chait
DEMPSEY
>>of $5000 with current components and worth every penny. I could
>>have just as easily blown the money at a crap table, with nothing to
>>show for it. My selection of parts produced a bicycle suitable for
>>my particular purposes. Call it luck, if you may, but all the parts
>>came together properly without a century of trial and error effort.
>>works, when in fact one ride convinces you that it does. To ride it
>>is to love it. Enough said. - Jim McNamara
>>
>Uh, maybe if you put the two bikes next to each other and measure
>the differences you will begin to see why they fell different. In
>any case, comparing a perfect, expensive, well thought out bike like
>the Merlin with a mass produced upper-middle class bike like the
>Centurion isn't a very fair comparison don't you think?
>Why not compare your Merlin with a Master Light?
Why does the production volume difference between these two bicycle frames
invalidate the comparison of two bicycles built around them? Prestige of
Does the prestige of ownership affect the ride quality of a bicycle?
I don't think that you meant to say that it did, so what WERE you trying to
say? You seem convinced that a Centurion, or other less prestigious brand
of bicycle, could certainly not be as pleasurable to ride as something like
a Merlin. How do you know that what you call 'well thought out' is not, in
fact, merely 'well differentiated from the commonplace?'
-Brian
--
DEMPSEY,BRIAN DAVID
Georgia Institute of Technology, Atlanta Georgia, 30332
uucp: ...!{decvax,hplabs,ncar,purdue,rutgers}!gatech!prism!ch89abe
Internet: ch8...@prism.gatech.edu
DEMPSEY
hau...@mbi.org writes:
>If this is
>>not due to frame compliance, then what else am I supposed to
>>attribute it to?
>Of course they have different characteristics! Two steel frames, unless
>identical, will have different characteristics. They have different length
>tubes, different angles, different masses, and different stiffnesses (and
>other variables I left out, no doubt).
>Since titanium is a stepping stone between aluminum and steel, a bigger
>difference in frames is noticed between a standard steel frame and an
>oversized aluminum one. The aluminum will probably be stiffer, yet
>lighter. This makes it more responsive, yet more comfortable (since comfort
>is related to mass). Of course there are many other variables - probably the
>most important of which is how well the frame fits the rider. A feeling of
>'oneness' with the bike cannot be obtained if the frame doesn't fit.
Stepping stone? What does 'stepping stone' mean metallurgically? Do you
know what you're talking about here? You sound like a bike salesman!
What is the relationship between comfort and mass, as you understand it?
Are you more 'comfortable' in the knowledge than you own a lightweight bicycle
than you would be owning a heavier one? I don't get it.
What value of the variable 'frame fitting the rider' yields the most comfort?
I'd bet a one-size-fits-you recumbent is more comfortable to coast along on
than some Cannondale 'Criterium' road frame that you'd say was a good fit for
a particular rider. Shall we assume, for the sake of your argument, that
recumbents don't 'fit' and disregard them? O.K. then, how about 'touring'
geometry bikes, is that unfair as well to consider? You're arguments' supports
are providing me a feeling of 'numbness.'
>The argument I (and Thomas, I think) was refuting was that aluminum frames
>have a harsher ride. This neither means nor implies that there isn't a
>noticeable difference in other ways. Certainly this will also be true of your
>titanium frame, but the differences result from many things, not just that
>it's made of titanium.
The argument you seem to be making is that one should pay attention to more
than just a frame material when selecting a bicycle. I can't imagine that
your point is not part of the general cyclists' consciousness, so why do you
bring it up? If you really want to emphasize that point, why not simply
state that the harshness people assign to certain named aluminum-framed
bicycles are not simply results of the fact that their frames are aluminum?
Many would ruch to agree and relate their delight with their aluminum-
framed bicycles of said certain make, but still others would report their
harsh experience on said certain make of bicycle.
I suppose that you've considered all of that, and tried to obfuscate the issue
by remaining so vague and friendly sounding. Bravo! YOU WIN!! SUPERLATIVE!!!
hau...@mbi.org
In article <5sou5h$d...@acmez.gatech.edu> ch8...@prism.gatech.edu (DEMPSEY) writes:
>From: ch8...@prism.gatech.edu (DEMPSEY)
>Subject: Re: Why do people think Alu frames are HARSHER? / One for Jobst ! / Tom K.
DEMPSEY wrote:
>Stepping stone? What does 'stepping stone' mean metallurgically? Do you
>know what you're talking about here? You sound like a bike salesman!
How so?? Although I've already provided an implied meaning of 'stepping
stone', I meant that it is (about halfway) between aluminum and steel, in
terms of stiffness to weight, strength to weight, and mass.
>What is the relationship between comfort and mass, as you understand it?
>Are you more 'comfortable' in the knowledge than you own a lightweight bicycle
>than you would be owning a heavier one? I don't get it.
That's clear enough. A lighter frame (and bike) will better conform to road
surface. Thus, it's more comfortable.
>What value of the variable 'frame fitting the rider' yields the most comfort?
>I'd bet a one-size-fits-you recumbent is more comfortable to coast along on
>than some Cannondale 'Criterium' road frame that you'd say was a good fit for
>a particular rider.
Recumbents? Now you're using Jobst's trick - changing the subject simply to
start an argument.
Shall we assume, for the sake of your argument, that
>recumbents don't 'fit' and disregard them? O.K. then, how about 'touring'
>geometry bikes, is that unfair as well to consider?
I don't recall writing anything that would mean or even imply that I wanted to
exclude 'touring' bikes, or even separate them from racing frames. I didn't
mention recumbents, and will not attempt to discuss them now. That would be
akin to discussing highwheelers - a totally different animal.
>I suppose that you've considered all of that, and tried to obfuscate the issue
>by remaining so vague and friendly sounding. Bravo! YOU WIN!! SUPERLATIVE!!!
Uh, oh, now being 'friendly sounding' is a liability, apparently. Quite
ironic, since I haven't been accused of being so 'friendly sounding' before!
Brian, what exactly is your point? You apparently want to argue, but don't
know what to argue about.
Rich
Mark Hickey
hau...@mbi.org writes...
>
>ch8...@prism.gatech.edu (DEMPSEY) writes:
>>What is the relationship between comfort and mass, as you understand it?
>>Are you more 'comfortable' in the knowledge than you own a lightweight
bicycle
>>than you would be owning a heavier one? I don't get it.
>
>That's clear enough. A lighter frame (and bike) will better conform to road
>surface. Thus, it's more comfortable.
Just a fine point here...
If the above statement is based on the fact that a bike frame with
lighter, thinner tubing will provide some sort of "suspension" that
will keep the bike in contact with the road, don't count on it.
From a theoretical standpoint, and to some ridiculously small
degree, yes. But realistically, no.
OTOH, a bike frame made out of solid spent uranium rods would
be the most comfortable bike possible. Its mass would tend to
isolate the rider from the road, much as a luxury car does the
same thing (well, compared to a Pinto - or Golf or whatever
econobox they drive in your part of the world). It wouldn't
be much fun to ride, but it WOULD be comfortable.
There, I hope I've confused things even more.... ;-)
Mark Hickey
Habanero Cycles
http://www.cynetfl.com/habanero/
Home of the $675 ti frame
pp00...@mindspring.com
In Article<tomkEEr...@netcom.com>, <to...@netcom.com> writes:
> Newsgroups: rec.bicycles.tech
> Path:
interramp.com!psinntp!news.idt.net!demos!news.maxwell.syr.edu!ix.netc
om.com!tomk
> From: to...@netcom.com (Thomas H. Kunich)
> Subject: Re: Why do people think Alu frames are HARSHER? / One for
Jobst ! / Tom K.
> Message-ID: <tomkEEr...@netcom.com>
> Organization: Netcom
> References: <33DE77...@uclink2.berkeley.eduREMOVE>
<tomkEEH...@netcom.com> <haubert.65...@mbi.org>
<NEWTNews.8709675...@pp000428.mindspring.com>
> Date: Mon, 11 Aug 1997 15:17:58 GMT
> Lines: 28
> Sender: to...@netcom17.netcom.com
>
> In article
<NEWTNews.8709675...@pp000428.mindspring.com>,
> <pp00...@mindspring.com> wrote:
>
> >With Cont GPs inflated to 130-135psi (which makes for a pretty
harsh
> >riding tire) the ride characteristics of my old Centurion Ironman
vs
> >my Spectrum (Merlin) titanium frame are unmistakable. If this is
> >not due to frame compliance, then what else am I supposed to
> >attribute it to? As far as "touchy after spending all that
money"
> >is concerned, I'm neither touchy nor concerned with the money
which
> >I feel was well spent. The current value of the bike is in
excess
> >of $5000 with current components and worth every penny. I could
> >have just as easily blown the money at a crap table, with nothing
to
> >show for it. My selection of parts produced a bicycle suitable
for
> >my particular purposes. Call it luck, if you may, but all the
parts
> >came together properly without a century of trial and error
effort.
> >There is little point in arguing over if the resulting package
> >works, when in fact one ride convinces you that it does. To ride
it
> >is to love it. Enough said. - Jim McNamara
> >
>
> Uh, maybe if you put the two bikes next to each other and measure
> the differences you will begin to see why they fell different. In
> any case, comparing a perfect, expensive, well thought out bike
like
> the Merlin with a mass produced upper-middle class bike like the
> Centurion isn't a very fair comparison don't you think?
>
> Why not compare your Merlin with a Master Light?
>
Tom,
I agree. The comparison is not entirely fair, nor would it be any
more so if the Master Light were thrown into the mix, and I didn't
have one at my disposal. It was not my intention to conduct a
definitive study so much as to assess the discernible differences
between the two bikes I had in my possession. When I still owned
the Ironman, I did put the two bikes next to one another, and they
weren't vastly different, but I realize that it doesn't take much of
a difference to produce a discernible difference in ride feel. One
ride convinced me that my Spectrum was a bike I would enjoy riding
much more than I did the Ironman. Many miles down the line, I still
feel this way. The geometry, and resulting fit, are more suitable
and dare I say the resilient nature of the framed imparts a gentler
feel that is all together more engaging. - Jim McNamara
trad...@rocketmail.com
This thread is getting out of hand.
Ride comfort is influenced by the following frame qualities,
forgive me if I miss any:
1. Preconceived notions. Research in judgement and decision making
has shown that when you get an idea in your head, it tends to stay
there. Corollary: if the media tells you a bike rides rough, it
will ride rough. I had the fortune of riding an early production
Klein (1984 touring Performance) before the media attacked C-dale,
and thought it a little smoother than my steel touring bike.
I now believe the difference, if there was one, to be in the lighter
weight of the Klein.
2. Mass, less being better. Suspension designers use the term
"unsprung weight ratio" to describe the relationship between
the parts bouncing up and down over bumps (the bike) to the parts
you're trying to hold level (your head, torso, etc.) In cars,
heavy chassis ride smoothly, heavy wheels don't.
Gary Klein "discovered" this concept in an engineering class,
(it's taught to everybody) and patented the concept. (gov't
stupidity at work :)
3. Sound, less being better. Researched extensively by car makers,
cars that don't make noises when going over bumps are perceived
as smooth riding. (I believe that this, combined with the
mass of early Cannonballs(dales) is responsible for the idea
that aluminum rides harsh.)
4. Wheelbase, less being worse. Two factors at work here.
When short chainstays put saddle directly over back wheel,
saddle goes up 1" when back wheel goes up 1". If saddle were
exactly between wheels, saddle would only go up 1/2".
Front to back rocking motions are lessened by longer wheelbase.
5. Damping. (PLEASE don't say dampening. Show the world you're more
literate than the marketing gurus at the car makers.) On a metal frame,
the paint damps more than the frame. This goes for Al, Ti, Steel,
and beryllium. With composite frames, the damping is not
significant when compared to the tires.
6. Vertical flex in any frame (even my 1987 Look, or the 979 Vitus
I almost bought) is small compared to tire compression.
(See numberous posts in this group)
Mick.
-------------------==== Posted via Deja News ====-----------------------
http://www.dejanews.com/ Search, Read, Post to Usenet
Thomas H. Kunich
In article <33EF8E...@fix.net>, Ed Chait <ech...@fix.net> wrote:
>
>When I mentioned "frequencies", I wasn't referring to anything auditory,
>but rather to vibration.
So was I.
> High frequency vibration, for instance, is
>something that lots of people find very annoying and harsh, including
>me. Is it not possible that these different frame materials transmit
>the road surface in different ways to the rider?
Yes, that was what I was saying. Steel "rings", aluminum "thunks"
and titanium and carbon fiber don't seem to do anything.
I just like the way steel rings beneath me on a good bike.
Thomas H. Kunich
In article <5sovf7$e...@acmez.gatech.edu>,
DEMPSEY <ch8...@prism.gatech.edu> wrote:
>Why does the production volume difference between these two bicycle frames
>invalidate the comparison of two bicycles built around them?
So, do you expect that one frame built by people who are trying to
build the best bicycle in the world might be different from one where
the idea is to pump out the largest number of bicycles for the lowest
possible price while maintaining the minimal quality standards imposed
by your marketing staff -- might be different in some minor respects?
In fact, Centurian (now Diamondback) are excellent bicycles for their
price and the market they are meant to address.
However, the tubing is heavier than necessary because that makes
weld quality issues less important. The geometry is meant to be all
things to all people and so the handling tends to be a bit on the
slow side for people used to more specialized machines. The butts
are generally longer, the welds coarser, the paint cheaper, the
graphics less inspired. The alignment is kept within wider tolerances
and the finish work on the frame is poorer compared to a Colnago
Master Light or a Merlin.
Is this a knock at Diamondback? Heck no, but if you want to compare
a MErlin with something you compare it to a bike designed by another
master craftsman who wants to build the best bike in the world. And
in Colnago's case they probably do.
And to put the subject back on track: if you ride a properly set up
Colnago Master Light (Steel), a Merlin and, say, a Pinarello Alu
you'll be hard pressed to tell any difference between them.
But even a mutton-head can tell the difference between a Merlin
and a Centurion Ironman.
Prestige of
>Does the prestige of ownership affect the ride quality of a bicycle?
>I don't think that you meant to say that it did, so what WERE you trying to
>say? You seem convinced that a Centurion, or other less prestigious brand
>of bicycle, could certainly not be as pleasurable to ride as something like
>a Merlin. How do you know that what you call 'well thought out' is not, in
>fact, merely 'well differentiated from the commonplace?'
>
hau...@mbi.org
In article <5spolh$r...@news1-alterdial.uu.net> mhi...@cynetfl.com (Mark Hickey) writes:
>From: mhi...@cynetfl.com (Mark Hickey)
>Subject: Re: Why do people think Alu frames are HARSHER? / One for Jobst ! / Tom K.
>hau...@mbi.org writes...
>>
>>That's clear enough. A lighter frame (and bike) will better conform to road
>>surface. Thus, it's more comfortable.
>Just a fine point here...
>If the above statement is based on the fact that a bike frame with
>lighter, thinner tubing will provide some sort of "suspension" that
>will keep the bike in contact with the road, don't count on it.
>From a theoretical standpoint, and to some ridiculously small
>degree, yes. But realistically, no.
>OTOH, a bike frame made out of solid spent uranium rods would
>be the most comfortable bike possible. Its mass would tend to
>isolate the rider from the road, much as a luxury car does the
>same thing (well, compared to a Pinto - or Golf or whatever
>econobox they drive in your part of the world). It wouldn't
>be much fun to ride, but it WOULD be comfortable.
I doubt it. A lighter bike is more comfortable than a heavy one because one's
body weight (sprung weight) keeps it on the road better. A heavier bike is
thrown up at the rider with more force, at every bump.
Rich
Matt O'Toole
Mark Hickey <mhi...@cynetfl.com> wrote in article
<5spolh$r...@news1-alterdial.uu.net>...
> OTOH, a bike frame made out of solid spent uranium rods would
> be the most comfortable bike possible. Its mass would tend to
> isolate the rider from the road, much as a luxury car does the
> same thing (well, compared to a Pinto - or Golf or whatever
> econobox they drive in your part of the world). It wouldn't
> be much fun to ride, but it WOULD be comfortable.
>
> There, I hope I've confused things even more.... ;-)
Yes, you have. Actaully, a uranium framed bike would be no better riding
than anything else. The mass itself does not isolate the rider from the
road. The suspension system does, and in this case, that's simply the
tires and saddle. It is not merely the extra mass that gives a luxury car
its smooth ride, but the suspension system. If mass were all that was
important, a cement truck would have the smoothest ride of all. Anyone who
has driven such trucks, as well as luxury cars, will tell you the luxury
car wins the ride quality contest.
Matt O.
pp00...@mindspring.com
In Article<5sovf7$e...@acmez.gatech.edu>, <ch8...@prism.gatech.edu>
writes:
> Path:
interramp.com!psinntp!news-ext.gatech.edu!gatech!smash.gatech.edu!pri
sm!prism!not-for-mail
> From: ch8...@prism.gatech.edu (DEMPSEY)
> Newsgroups: rec.bicycles.tech
> Subject: Re: Why do people think Alu frames are HARSHER? / One for
Jobst ! / Tom K.
> Date: 12 Aug 1997 02:22:31 -0400
> Organization: Georgia Institute of Technology
> Lines: 37
> Message-ID: <5sovf7$e...@acmez.gatech.edu>
> References: <33DE77...@uclink2.berkeley.eduREMOVE>
<tomkEEH...@netcom.com> <haubert.65...@mbi.org>
<NEWTNews.8709675...@pp000428.mindspring.com>
<tomkEEr...@netcom.com>
> NNTP-Posting-Host: ch8...@acmez-prism.gatech.edu
>
> to...@netcom.com (Thomas H. Kunich) writes:
> >>I feel was well spent. The current value of the bike is in
excess
> >>of $5000 with current components and worth every penny. I could
> >>have just as easily blown the money at a crap table, with
nothing to
> >>show for it. My selection of parts produced a bicycle suitable
for
> >>my particular purposes. Call it luck, if you may, but all the
parts
> >>came together properly without a century of trial and error
effort.
> >>There is little point in arguing over if the resulting package
> >>works, when in fact one ride convinces you that it does. To
ride it
> >>is to love it. Enough said. - Jim McNamara
> >>
>
> >Uh, maybe if you put the two bikes next to each other and measure
> >the differences you will begin to see why they fell different. In
> >any case, comparing a perfect, expensive, well thought out bike
like
> >the Merlin with a mass produced upper-middle class bike like the
> >Centurion isn't a very fair comparison don't you think?
>
> >Why not compare your Merlin with a Master Light?
>
> Why does the production volume difference between these two
bicycle frames
> invalidate the comparison of two bicycles built around them?
Prestige of
> Does the prestige of ownership affect the ride quality of a
bicycle?
> I don't think that you meant to say that it did, so what WERE you
trying to
> say? You seem convinced that a Centurion, or other less
prestigious brand
> of bicycle, could certainly not be as pleasurable to ride as
something like
> a Merlin. How do you know that what you call 'well thought out'
is not, in
> fact, merely 'well differentiated from the commonplace?'
>
> -Brian
>
>
> --
> DEMPSEY,BRIAN DAVID
> Georgia Institute of Technology, Atlanta Georgia, 30332
> uucp:
..!{decvax,hplabs,ncar,purdue,rutgers}!gatech!prism!ch89abe
> Internet: ch8...@prism.gatech.edu
Brian,
Please note that your reply was directed to two different authors
Being one of them, I will address that portion which was directed my
way. Contrary to what you assume, I do not contend that a less
prestigious brand of bicycle, by default is necessarily less
pleasurable to ride, but I do stand by my contention that my
Centurion Ironman was unequivocally less pleasurable to ride than my
Specturm titanium bike. There is little point in engaging in a
debate over an issue which has subsequently been resolved
experientially. Just for the record, however, I am quite
comfortable with prestige of ownership (curb appeal), but I also
realize that expense does not equate to ride quality. As concerns
"well thought out" and "well differentiated from the commonplace",
these are certainly not mutually exclusive categories. Suffice it
to say that when something works well, that this is generally
attributable to something having been well thought out, and in this
particular example, "well differentiated from the commonplace" also
happens to apply. - I suspect from your tone, that you too consider
yourself "well differentiated from the commonplace". Brian you're a
legend in your own mind! - Jim McNamara.
Thomas H. Kunich
In article <NEWTNews.8713995...@pp000428.mindspring.com>,
<pp00...@mindspring.com> wrote:
>
>I agree. The comparison is not entirely fair, nor would it be any
>more so if the Master Light were thrown into the mix, and I didn't
>have one at my disposal. It was not my intention to conduct a
>definitive study so much as to assess the discernible differences
>between the two bikes I had in my possession. When I still owned
>the Ironman, I did put the two bikes next to one another, and they
>weren't vastly different, but I realize that it doesn't take much of
>a difference to produce a discernible difference in ride feel. One
>ride convinced me that my Spectrum was a bike I would enjoy riding
>much more than I did the Ironman. Many miles down the line, I still
>feel this way. The geometry, and resulting fit, are more suitable
>and dare I say the resilient nature of the framed imparts a gentler
>feel that is all together more engaging. - Jim McNamara
>
Just to give you something to think about: I had (stolen) a Basso
Gap with DuraAce STI and my Colnago Super with Campi Super Record.
Stood next to each other, the only thing I could tell different on
each was the color. There were very slight differences in the head
angle. These bikes were so different feeling that they might as
well have been from different planets.
hau...@mbi.org
In article <tomkEE...@netcom.com> to...@netcom.com (Thomas H. Kunich) writes:
>From: to...@netcom.com (Thomas H. Kunich)
Matt O'Toole
trad...@rocketmail.com wrote in article <8714069...@dejanews.com>...
> This thread is getting out of hand.
Yes. It would be nice if those involved would read the FAQ, or at least
some of the previous posts, where they'd probably find their questions have
already been answered.
> Ride comfort is influenced by the following frame qualities,
> forgive me if I miss any:
> 1. Preconceived notions. Research in judgement and decision making
> has shown that when you get an idea in your head, it tends to stay
> there. Corollary: if the media tells you a bike rides rough, it
> will ride rough. I had the fortune of riding an early production
> Klein (1984 touring Performance) before the media attacked C-dale,
> and thought it a little smoother than my steel touring bike.
I'm glad you used the word "preconceived." It is true that ride quality is
often thought, not felt.
> I now believe the difference, if there was one, to be in the lighter
> weight of the Klein.
Now you're swimming in dangerous waters.
> 2. Mass, less being better. Suspension designers use the term
> "unsprung weight ratio" to describe the relationship between
> the parts bouncing up and down over bumps (the bike) to the parts
> you're trying to hold level (your head, torso, etc.) In cars,
> heavy chassis ride smoothly, heavy wheels don't.
With cars, but not really with bicycles. It does make more difference on a
mountain bike, where the bike and rider are travelling over wildly
undulating terrain, and low-frequency, high-amplitude bumps come one after
the other. The rider may not even be in the saddle, but hovering over it,
using his legs and arms as the suspension. In this case, the difference in
sprung-to-unsprung weight ratios can be felt. Lighter bikes are less
tiring to ride over such terrain, as the rider has less mass to control.
On the road, however, the situation is not the same. Most of the time, the
rider is in the saddle. Most of the bumps are much lower amplitude, and the
rider's arms and legs are not functioning as suspension. The lower
amplitude bump motions are not being controlled by the long muscles and
motions of the arms and legs. They're absorbed by the tires, saddle,
handlebar tape, gloves, and the soft tissues of the palms of the hands, and
the rider's bottom.
> Gary Klein "discovered" this concept in an engineering class,
> (it's taught to everybody) and patented the concept. (gov't
> stupidity at work :)
I believe Klein's patent has to do with the rigidity of the frame, not the
weight.
> 3. Sound, less being better. Researched extensively by car makers,
> cars that don't make noises when going over bumps are perceived
> as smooth riding. (I believe that this, combined with the
> mass of early Cannonballs(dales) is responsible for the idea
> that aluminum rides harsh.)
I think this is the key to this whole fiasco. Again, however, it has
nothing to do with mass. (Didn't you just say that lighter bikes ride
smoother, anyway?) An aluminum bike's large tubes resonate loudly,
compared to the small tubes of a steel bike. Therefore, every rattle,
squeak, and pop on an aluminum bike is heard. With so much noise going on,
a rider may think it's because the bike is riding more harshly, and causing
more things to rattle.
> 4. Wheelbase, less being worse. Two factors at work here.
> When short chainstays put saddle directly over back wheel,
> saddle goes up 1" when back wheel goes up 1". If saddle were
> exactly between wheels, saddle would only go up 1/2".
> Front to back rocking motions are lessened by longer wheelbase.
If you think about it, the differences in chainstay dimension are very
small, and the resulting difference in vertical motion is even smaller.
The difference felt here is due to differences in weight distribution,
front to rear, and body position. A bike with short chainstays often has
more weight placed on the rear wheel. Thus, when going over a bump, the
rider feels more of it under his butt, rather than through his arms.
Placing more of the rider's weight over the front wheel allows the rider to
absorb more of the bump with his arms. Also, leaning the rider forward
more takes some weight off the saddle, and puts him in a more dynamic
position, where bumps are absorbed more by the arms and legs.
You may be correct about the rocking motions with respect to wheelbase.
However, the difference in wheelbase between various bikes seems
insignificant to me compared to the much wider variation in rider sizes.
> 5. Damping. (PLEASE don't say dampening. Show the world you're more
> literate than the marketing gurus at the car makers.)
It's what you have to say that's important, not how you say it. Some
well-repected race car designers say "dampening." Forner president Carter
is well known to be a very literate man, and he says "nucular."
> On a metal frame,
> the paint damps more than the frame. This goes for Al, Ti, Steel,
> and beryllium. With composite frames, the damping is not
> significant when compared to the tires.
The flex isn't significant with any of these, so the damping isn't, either.
> 6. Vertical flex in any frame (even my 1987 Look, or the 979 Vitus
> I almost bought) is small compared to tire compression.
> (See numberous posts in this group)
The word is "insignificant."
Matt O.
Ulrich Elsner
Matt O'Toole <ma...@deltanet.com> wrote:
>
>Mark Hickey <mhi...@cynetfl.com> wrote
>> OTOH, a bike frame made out of solid spent uranium rods would
>> be the most comfortable bike possible. Its mass would tend to
>>
>> There, I hope I've confused things even more.... ;-)
>
>Yes, you have. Actaully, a uranium framed bike would be no better riding
>than anything else. The mass itself does not isolate the rider from the
>road. The suspension system does, and in this case, that's simply the
>tires and saddle. It is not merely the extra mass that gives a luxury car
>its smooth ride, but the suspension system. If mass were all that was
>important, a cement truck would have the smoothest ride of all. Anyone who
>has driven such trucks, as well as luxury cars, will tell you the luxury
>car wins the ride quality contest.
Of course, with car vs. truck, not everything else is equal. So to add
just one data point:
Judging merely from experience (and not trying to explain the phenomena),
my touring bike rides _much_ nicer with 50lb weight loaded onto it than
without. So: same geometry, same frame, same tires, same everything
except for 4 panniers and suddenly the ride is much smoother. The bike
rides like it is on rails. Unloaded, it just rides "normal", like other
bikes as well.
If I didn't have to accelerate that thing (or ride up hills) , I'd just
fill my panniers with sand and ride the loaded bike all the time.
(No smilie!). Due to the front lowrider, one needs a "stronger hand" to
steer but it's easy to adapt to that.
--
Ulrich Elsner, Fak. fuer Mathematik, TU Chemnitz, D-09107 Chemnitz, Germany
Mark Hickey
>Matt O'Toole <ma...@deltanet.com> wrote:
>>
>>Mark Hickey <mhi...@cynetfl.com> wrote
>>
>>> OTOH, a bike frame made out of solid spent uranium rods would
>>> be the most comfortable bike possible. Its mass would tend to
>>> isolate the rider from the road, [...] It wouldn't
>>> be much fun to ride, but it WOULD be comfortable.
>>>
>>> There, I hope I've confused things even more.... ;-)
>>
>>Yes, you have. Actaully, a uranium framed bike would be no better riding
>>than anything else. The mass itself does not isolate the rider from the
>>road. The suspension system does, and in this case, that's simply the
>>tires and saddle. It is not merely the extra mass that gives a luxury car
>>its smooth ride, but the suspension system. If mass were all that was
>>important, a cement truck would have the smoothest ride of all. Anyone who
>>has driven such trucks, as well as luxury cars, will tell you the luxury
>>car wins the ride quality contest.
Ulrich Elsner stated the difference in a very real way (with his
WAY heavy panniers). The difference is going to be in the "suspension"
otherwise known as "tires". Adding weight will limit the vertical
excursions of the bike, thereby improving the "ride".
Yep, my old Pinto wagon rode pretty good on the way home from
college, loaded to the gunwales with my worldly possessions.
That was, of course, the only time it really rode well....
And if you took that luxury car and chopped it down to the frame
and driver's seat, it would ride like a log wagon, since the suspension
was designed for much more weight.
Now, let's talk about how fast that spent uranium bike is gonna
go down hills..... ;-)
pp00...@mindspring.com
In Article<haubert.67...@mbi.org>, <hau...@mbi.org> writes:
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haubert
> From: hau...@mbi.org
> Newsgroups: rec.bicycles.tech
> Subject: Re: Why do people think Alu frames are HARSHER? / One for
Jobst ! / Tom K.
> Date: Tue, 12 Aug 1997 15:52:26 UNDEFINED
> Organization: Michigan Biotechnology Institute
> Lines: 33
> Message-ID: <haubert.67...@mbi.org>
> References: <33DE77...@uclink2.berkeley.eduREMOVE>
<NEWTNews.8707921...@pp000428.mindspring.com>
<tomkEEG...@netcom.com>
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> X-Newsreader: Trumpet for Windows [Version 1.0 Rev B]
>
> In article <5spolh$r...@news1-alterdial.uu.net> mhi...@cynetfl.com
(Mark Hickey) writes:
> >From: mhi...@cynetfl.com (Mark Hickey)
> >Subject: Re: Why do people think Alu frames are HARSHER? / One
for Jobst ! / Tom K.
> >Date: 12 Aug 1997 13:32:33 GMT
>
> >hau...@mbi.org writes...
> >>
>
>
> >>That's clear enough. A lighter frame (and bike) will better
conform to road
> >>surface. Thus, it's more comfortable.
>
> >Just a fine point here...
>
> >If the above statement is based on the fact that a bike frame
with
> >lighter, thinner tubing will provide some sort of "suspension"
that
> >will keep the bike in contact with the road, don't count on it.
> >From a theoretical standpoint, and to some ridiculously small
> >degree, yes. But realistically, no.
>
> >OTOH, a bike frame made out of solid spent uranium rods would
> >be the most comfortable bike possible. Its mass would tend to
> >isolate the rider from the road, much as a luxury car does the
> >same thing (well, compared to a Pinto - or Golf or whatever
> >econobox they drive in your part of the world). It wouldn't
> >be much fun to ride, but it WOULD be comfortable.
>
> I doubt it. A lighter bike is more comfortable than a heavy one
because one's
> body weight (sprung weight) keeps it on the road better. A
heavier bike is
> thrown up at the rider with more force, at every bump.
>
> Rich
>
Just a slight interjection here. I once saw a bike in Copenhagen
which caught my attention as it was the samllest diameter tubing I
had ever seen, or at least I thought it was tubing. When I went into
a bike shop up the street, I asked the shop owner if he knew
anything about this peculiar bike. He said that he had just
finished doing some maintenance on it and claimed that it was a very
old bike, handed down from father to son, and indicated that the
frame was constructed of solid steel rods. He claimed that it was
quite heavy and very whippy. I got the distinct impression that,
the compliant nature (resiliency) of the frame might have provided a
rather springy ride, but one would have to take it for a spin around
the block to verify this. I would like to have ridden it, but
unfortunately I never had the opportunity. - Jim McNamara
Robert Turnbull
After reading many of the posts in this thread, I have come to
the conclusion none of the replys have really addressed the appropriate
physics. Static experiments do not necessarily predict dynamic behavior.
What one feels as road shock is not displacement but rather I believe that
it is the derivative of the acceleration. Let me pose an experiment. A
cyclist is riding along on a smooth pavement and comes to a 1 cm vertical
step and then the pavement becomes smooth again. No matter what frame
he has the cyclist is going to end up 1 cm higher than when he started, that
is not at issue. Also not at issue is the fact that there will be a
wave set up in the frame. If there is no dispersion in the frame the
acceleration at the seat and handlebars will have the same rise-time as
at the axles. However if thje frame has any dispersion the rise-time
at the seat and handlebars will be greater than at the axles and the rider
will feel less shock.
Has anybody done this experiment? Or has anybody done calculations on
sound wave propagation in bike frames?
I don't pretend to know the answers to this. If I did I wouldn't be
asking the questions.
Bob Turnbull
boyd
On 12 Aug 1997, Matt O'Toole wrote:
>
>
> Mark Hickey <mhi...@cynetfl.com> wrote in article
> <5spolh$r...@news1-alterdial.uu.net>...
>
> > OTOH, a bike frame made out of solid spent uranium rods would
> > be the most comfortable bike possible. Its mass would tend to
...
> > be much fun to ride, but it WOULD be comfortable.
> >
> > There, I hope I've confused things even more.... ;-)
>
> Yes, you have. Actaully, a uranium framed bike would be no better riding
> than anything else. The mass itself does not isolate the rider from the
...
> has driven such trucks, as well as luxury cars, will tell you the luxury
> car wins the ride quality contest.
>
> Matt O.
>
And anyone who has ridden a loaded touring bike would agree with Mark H.
The supension (tires) is much more effective at isolating the rider when
there is a lot of mass in, or mounted on, the frame.
Mark <bo...@cs.unca.edu>
Thomas H. Kunich
In article <NEWTNews.8714850...@pp000428.mindspring.com>,
<pp00...@mindspring.com> wrote:
>> Just to give you something to think about: I had (stolen) a Basso
>> Gap with DuraAce STI and my Colnago Super with Campi Super Record.
>> Stood next to each other, the only thing I could tell different on
>> each was the color. There were very slight differences in the head
>> angle. These bikes were so different feeling that they might as
>> well have been from different planets.
>>
>
>Tom,
>
>How about some detail in support of your observation that "these
>bikes were so different feeling that they might as well have been
>from different planets". Curious minds want to know. - Jim McNamara
The Colnago Super is the penultimate European domestique racing
bike with a long top tube, a low aerodynamic position and a very
laid back feeling. Last Sunday we did a 30+ mile ride through lots
of traffic lights and still averaged 17.5 mph despite three flats
in the group.
The Basso felt a much better bike. It steered much quicker rode
with less bounce (probably due to the SP tubing in spots) and
wouldn't track for beans around corners. Holding high averages
in criteriums was easy but holding high averages in road races
wasn't that easy, even though I much preferred the Basso for long
rides since it had a more solid feel.
Sitting next to one another the differences were so slight that you
had to know where to look. The Basso Gap had a steep head angle of
75 degrees while the Colnago is between 72 and 73 degrees. Hanging
vertically from two hooks in my garage they had the same handlebar
plascement, the same seat placement, the same wheelbase, chainstay
length, cockpit center. Same chrome, same lugs, one was red the other
blue.
Joshua_Putnam
>trad...@rocketmail.com wrote in article <8714069...@dejanews.com>...
>> Ride comfort is influenced by the following frame qualities,
>> forgive me if I miss any:
>> 1. Preconceived notions. Research in judgement and decision making
>> has shown that when you get an idea in your head, it tends to stay
>> there. Corollary: if the media tells you a bike rides rough, it
>> will ride rough. I had the fortune of riding an early production
>> Klein (1984 touring Performance) before the media attacked C-dale,
>> and thought it a little smoother than my steel touring bike.
>I'm glad you used the word "preconceived." It is true that ride quality is
>often thought, not felt.
Before the anti-Cannondale movement, most people I talked to
"knew" that aluminum frames were "soft" and "noodly" because the
common aluminum bikes were Alans and Vituses, not Cannondales and
Kleins. They misattributed the flex to the material rather than
the overall frame design and materials combined.
>> 3. Sound, less being better. Researched extensively by car makers,
>> cars that don't make noises when going over bumps are perceived
>> as smooth riding. (I believe that this, combined with the
>> mass of early Cannonballs(dales) is responsible for the idea
>> that aluminum rides harsh.)
>I think this is the key to this whole fiasco. Again, however, it has
>nothing to do with mass. (Didn't you just say that lighter bikes ride
>smoother, anyway?) An aluminum bike's large tubes resonate loudly,
>compared to the small tubes of a steel bike. Therefore, every rattle,
>squeak, and pop on an aluminum bike is heard. With so much noise going on,
>a rider may think it's because the bike is riding more harshly, and causing
>more things to rattle.
I've occasionally wondered whether any of the manufacturers have
investigated sound damping in frames. In the car example, light
weight drive lines make a lot more noise than heavy ones, a
problem sometimes addressed with a cardboard tube iside the
driveline.
>> 4. Wheelbase, less being worse. Two factors at work here.
>> When short chainstays put saddle directly over back wheel,
>> saddle goes up 1" when back wheel goes up 1". If saddle were
>> exactly between wheels, saddle would only go up 1/2".
>> Front to back rocking motions are lessened by longer wheelbase.
>If you think about it, the differences in chainstay dimension are very
>small, and the resulting difference in vertical motion is even smaller.
This is true of mass-market bikes, with maybe 4cm difference
between crit bikes and average touring bikes, but there are some
specialty touring bikes with extremely long chainstays -- if I'm
not misremembering, Arvon makes a model with stays 6" longer
than the longest stock stays from Columbus or Reynolds,
specifically to lengthen wheelbase.
--
Jo...@WolfeNet.com is Joshua Putnam / P.O. Box 13220 / Burton, WA 98013
"My other bike is a car."
http://www.wolfenet.com/~josh
Matt O'Toole
Mark Hickey <mhi...@cynetfl.com> wrote in article
<5sqojj$c...@news1-alterdial.uu.net>...
> Ulrich Elsner stated the difference in a very real way (with his
> WAY heavy panniers). The difference is going to be in the "suspension"
> otherwise known as "tires". Adding weight will limit the vertical
> excursions of the bike, thereby improving the "ride".
You could get the same effect on your unloaded touring bike by letting some
air out of the tires, don't you think?
> Now, let's talk about how fast that spent uranium bike is gonna
> go down hills..... ;-)
As Mr. Springer would say, "Don't *even* go there!"
Matt O.
pp00...@mindspring.com
In Article<tomkEEt...@netcom.com>, <to...@netcom.com> writes:
> Newsgroups: rec.bicycles.tech
> Path:
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> From: to...@netcom.com (Thomas H. Kunich)
> Subject: Re: Why do people think Alu frames are HARSHER? / One for
Jobst ! / Tom K.
> Message-ID: <tomkEEt...@netcom.com>
> Organization: Netcom
> References: <33DE77...@uclink2.berkeley.eduREMOVE>
<NEWTNews.8709675...@pp000428.mindspring.com>
<tomkEEr...@netcom.com>
<NEWTNews.8713995...@pp000428.mindspring.com>
> Date: Tue, 12 Aug 1997 15:21:56 GMT
> Sender: to...@netcom17.netcom.com
> Lines: 25
DEMPSEY
hau...@mbi.org writes:
>>From: mhi...@cynetfl.com (Mark Hickey)
>>Subject: Re: Why do people think Alu frames are HARSHER? / One for Jobst ! / Tom K.
>>Date: 12 Aug 1997 13:32:33 GMT
>>hau...@mbi.org writes...
>>>
Rich wrote:
>>>That's clear enough. A lighter frame (and bike) will better conform to
road
>>>surface. Thus, it's more comfortable.
and then:
>I doubt it. A lighter bike is more comfortable than a heavy one because one's
>body weight (sprung weight) keeps it on the road better. A heavier bike is
>thrown up at the rider with more force, at every bump.
>Rich
What is the source of this upward force that knows how heavy your bike is
and throws it up at you differently based upon that knowledge? Are the rider's
forearm muscles sprung or unsprung weight? All this is to say - what you're
spouting here is nonsensical. Are you serious here? Oh, ya got my goat here,
I guess you deserved the laugh at my expense - I was assuming that you were
actually trying to advance an explanation for a 'harsh' ride resultng from
some peculiar bicycle frames.
-Brian
--
DEMPSEY,BRIAN DAVID
Georgia Institute of Technology, Atlanta Georgia, 30332
pp00...@mindspring.com
In Article<3408ec6f...@nntp.erinet.com>, <da...@erinet.com> writes:
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> From: da...@erinet.com
> Newsgroups: rec.bicycles.tech
> Subject: Re: Why do people think Alu frames are HARSHER? / One for Jobst ! / Tom K.
> Date: Thu, 14 Aug 1997 11:39:59 GMT
> Organization: EriNet Online 513 436-1700 (Voice)
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>
> >. Call it luck, if you may, but all the parts
> >>came together properly without a century of trial and error effort.
> >>There is little point in arguing over if the resulting package
> >>works, when in fact one ride convinces you that it does. To ride it
> >>is to love it. Enough said. - Jim McNamara
> >>
> >
> >Uh, maybe if you put the two bikes next to each other and measure
> >the differences you will begin to see why they fell different. In
> >any case, comparing a perfect, expensive, well thought out bike like
> >the Merlin with a mass produced upper-middle class bike like the
> >Centurion isn't a very fair comparison don't you think?
> >
> >Why not compare your Merlin with a Master Light?
>
> Why make either comparison? Except for differences in frame geometry
> or components, it's unlikely that you would be able to tell the
> difference. Since the discussion "subject" dealt with frames,
> component selection really isn't the topic. And a particular frame
> geometry is more a matter of choice than manufacturing economics.
>
> Try to find a copy of the December, 1996 issue of _Bicycle Guide_
> magazine. In that issue, the editors tested 7 Italian frames built by
> Antonio Mondonico. The frames were identical in all respects, except
> that they were built with Aelle, Cromor, Thron, Brain, SLX, Neuron and
> EL-OS tubesets from Columbus. Each bike was the same size and equipped
> with the same components. The bikes were "numbered" but otherwise
> were not distinquishable. This is about as close to a "blind test" as
> you'll get on bicycles.
>
> And the results? The bikes were just about identical. To quote
the
> article " . . . the personality of a bike is determined much more
by
> fit, frame geometry and components than by what kind of tubing
lies
> under the paint."
>
> BTW, the _frame_ weight of the tested bicycles ranged from 220g
> (EL-OS and Neuron) to 300g (Thron and Aelle). The 1996 price
ranges
> on the frames was $460 (Aelle) to $1275 (EL-OS) -- they would be
even
> more today. Except for bragging rights, it's unclear what you get
for
> the greater expenditure.
>
> .............dh
>
An interesting point, but I recall a similar test which was
conducted with identical GT bikes constructed of aluminum, steel,
and titanium with differing results. Testers observed discernible
differences in between the bikes. I believe the results were
published in a magazine no longer in print ... RoadBike Action. -
Jim McNamara
John Getsoian
>And anyone who has ridden a loaded touring bike would agree with Mark H.
>The supension (tires) is much more effective at isolating the rider when
>there is a lot of mass in, or mounted on, the frame.
>
For the same effect you could just unload the bike and let some air out of your tires ;-)
-regards
John Getsoian
[jget...@compuserve.com
or sls...@umich.edu]
Jim Chinnis
ch8...@prism.gatech.edu (DEMPSEY) wrote:
>I was assuming that you were
>actually trying to advance an explanation for a 'harsh' ride resultng from
>some peculiar bicycle frames.
>
> -Brian
I'm kinda new here and not a mechanical engineer, either, but I
must say that Brian's frustration over the lack of any reasonable
arguments about how different frame materials could affect
harshness is understandable.
Getting back into bicycling after a long lapse, I recently bought
a new bike. The sales people talked me out of aluminum on the
grounds of "harshness." Since then, I have wondered what on earth
they could have meant.
Modeling a rider/bike combination rolling down a less-than-smooth
path is not simple. But "harshness" must have to do with the feel
of the bike at the contact points between bike and rider. Metal
transmits vibration extremely well. Very low frequencies, say 10
Hz (cycles per second), are transmitted without any noticeable
degradation, regardless of the type of metal. Differences occur
only when frequencies get well into the audible range.
I think the harshness question boils down to asking whether or
not the differences among frame materials makes any noticeable
difference in the transmission of audible frequencies to the
rider's hands, feet, or derriere. While I suppose that some frame
materials and geometries might have some resonances (might "sing"
at certain frequencies), I find it hard to believe that this
could differ enough or be severe enough to make it through grips
and gloves, shoes and socks, and seat and padded shorts. If that
were the case, people should hear an aluminimun bike before it
came into view!
But what do I know? Maybe there's a mechanical engineer out there
with a background in vibratory modes of complex structures. I
know enough to know that the problem is a tough one when
addressed with any precision.
But I wish I'd bought the Al bike.
--
If replying by email, use the following address without the X:
Jim Chinnis Xjch...@earthlink.net Manassas, VA USA
DEMPSEY
to...@netcom.com (Thomas H. Kunich) writes:
>In article <5sovf7$e...@acmez.gatech.edu>,
>DEMPSEY <ch8...@prism.gatech.edu> wrote:
>>Why does the production volume difference between these two bicycle frames
>>invalidate the comparison of two bicycles built around them?
to...@netcom.com wrote:
>So, do you expect that one frame built by people who are trying to
>build the best bicycle in the world might be different from one where
>the idea is to pump out the largest number of bicycles for the lowest
>possible price while maintaining the minimal quality standards imposed
>by your marketing staff -- might be different in some minor respects?
Although I can't imagine that Merlin is not interested in 'pumping out' a
larger number of bicycles by being able to build them more quickly, nor that
the marketing staff at Centurion specified the minimum standard of quality
for their bicycles, nor that the Centruion and Merlin are not different in
some respects, it remains to be clarified WHICH, if any of these differences
are to blame for the difference in ride quality we expect to have when these
frames are built into bicycles and are ridden.
to...@netcom.com wrote:
>However, the tubing is heavier than necessary because that makes
>weld quality issues less important. The geometry is meant to be all
>things to all people and so the handling tends to be a bit on the
>slow side for people used to more specialized machines. The butts
>are generally longer, the welds coarser, the paint cheaper, the
>graphics less inspired. The alignment is kept within wider tolerances
>and the finish work on the frame is poorer compared to a Colnago
>Master Light or a Merlin.
How did 'handling' sneak in here? I thought we were discussing ride comfort
or quality. There's no doubt that there are differences between a Merlin
and a Centurion, but I don't think you mean to suggest that inspired graphics,
better finish work, or weld quality (weren't most Centurions brazed - never
mind) are contributing to a less 'harsh' ride. Other than what you perceive
as the company goals of Merlin and Centurion, what do you think is the explana-
tion for Jim's perception of a better 'ride quality,' - a less 'harsh' one -
while riding his Merlin?
to...@netcom.com wrote:
>And to put the subject back on track: if you ride a properly set up
>Colnago Master Light (Steel), a Merlin and, say, a Pinarello Alu
>you'll be hard pressed to tell any difference between them.
>But even a mutton-head can tell the difference between a Merlin
>and a Centurion Ironman.
You're so certain, Tom, but you offer no explanation as to why this phenomena
exists. A mutton-head who hasn't ridden bikes around all of these frames can
see your conviction, but not your point - why do some frames ride 'harsh' and
others not?
pp00...@mindspring.com
In Article<5suflt$h...@acmey.gatech.edu>, <ch8...@prism.gatech.edu> writes:
> Path: interramp.com!psinntp!news.idt.net!demos!news.maxwell.syr.edu!howland.erols.net!news-ext.gatech.edu!gatech!smash.gatech.edu!prism!prism!not-for-mail
> From: ch8...@prism.gatech.edu (DEMPSEY)
> Newsgroups: rec.bicycles.tech
> Subject: Re: Why do people think Alu frames are HARSHER? / One for Jobst ! / Tom K.
> Date: 14 Aug 1997 04:29:49 -0400
> Organization: Georgia Institute of Technology
> Lines: 64
> Message-ID: <5suflt$h...@acmey.gatech.edu>
> References: <33DE77...@uclink2.berkeley.eduREMOVE>
<NEWTNews.8713995...@pp000428.mindspring.com>
<tomkEEt...@netcom.com>
<NEWTNews.8714850...@pp000428.mindspring.com>
<tomkEEu...@netcom.com>
> NNTP-Posting-Host: ch8...@acmey-prism.gatech.edu
>
> to...@netcom.com (Thomas H. Kunich) writes:
>
> Tom Kunich wrote:
>
> >>> Just to give you something to think about: I had (stolen) a
Basso
> >>> Gap with DuraAce STI and my Colnago Super with Campi Super
Record.
> >>> Stood next to each other, the only thing I could tell
different on
> >>> each was the color. There were very slight differences in the
head
> >>> angle. These bikes were so different feeling that they might
as
> >>> well have been from different planets.
> >>>
>
> Jim McNamara wrote:
>
> >>How about some detail in support of your observation that "these
> >>bikes were so different feeling that they might as well have
been
> >>from different planets". Curious minds want to know. - Jim
McNamara
>
> Tom Kunich wrote:
>
> >The Colnago Super is the penultimate European domestique racing
> >bike with a long top tube, a low aerodynamic position and a very
> >laid back feeling. Last Sunday we did a 30+ mile ride through
lots
> >of traffic lights and still averaged 17.5 mph despite three flats
> >in the group.
>
> Although a true bike expert and a blazing rider, Tom is not much
help so far
> in distinguishing the different ride quality or smoothness between
these
> extra-terrestrial bicycle frames.
>
> >The Basso felt a much better bike. It steered much quicker rode
> >with less bounce (probably due to the SP tubing in spots) and
> >wouldn't track for beans around corners. Holding high averages
> >in criteriums was easy but holding high averages in road races
> >wasn't that easy, even though I much preferred the Basso for long
> >rides since it had a more solid feel.
>
> I can understand how a bike that wont track for 'beans' around
corners would
> make it easy for holding high 'averages' in criteriums, Tom.
Things are
> really making sense so far concerning ride quality or smoothness.
Is 'solid'
> on the 'harsh' scale or no? Your terminology so far has been
vague and
> succinct enough to grant you the lassitude needed to imagine that
maybe it is,
> and that you are still, therefore trying to be helpful.
>
> >Sitting next to one another the differences were so slight that
you
> >had to know where to look. The Basso Gap had a steep head angle
of
> >75 degrees while the Colnago is between 72 and 73 degrees.
Hanging
> >vertically from two hooks in my garage they had the same
handlebar
> >plascement, the same seat placement, the same wheelbase,
chainstay
> >length, cockpit center. Same chrome, same lugs, one was red the
other
> >blue.
>
> Did these comparisons change when you took them down and rode
them? What
> influence on the 'harsh'ness of the ride did color have, if any?
> I'm falling asleep.
>
> -Brian
>
>
> --
> DEMPSEY,BRIAN DAVID
> Georgia Institute of Technology, Atlanta Georgia, 30332
> uucp:
..!{decvax,hplabs,ncar,purdue,rutgers}!gatech!prism!ch89abe
> Internet: ch8...@prism.gatech.edu
Brian,
"What influence on the 'harsh' ness of the ride did color have, if
any?" ... I presume this to have been a rhetorical question. You
seem to be you overwhelmed by an obsession to argue just for the
sake of arguement, entangled in a web of your own perceived, obsucre
eloquence. Count me among those who are not smitten by your
sarcastic, insipid, verbosity. I know, Brian ... there I go
moderating, again. - Jim McNamara
DEMPSEY
Ed Chait wrote:
>>When I mentioned "frequencies", I wasn't referring to anything auditory,
>>but rather to vibration.
O.K. Ed, well can you tell me or at least GUESS the approximate frequencies
of these inaudible vibrations you're picking up?
Tom Kunich wrote:
>So was I.
Same question to you, Tom...
Ed Chati wrote:
>> High frequency vibration, for instance, is
>>something that lots of people find very annoying and harsh, including
>>me. Is it not possible that these different frame materials transmit
>>the road surface in different ways to the rider?
What do you mean by high frequency? Which do you find most 'harsh?'
Tom Kunich wrote:
>Yes, that was what I was saying. Steel "rings", aluminum "thunks"
>and titanium and carbon fiber don't seem to do anything.
I assume that you don't mean to refer to simply the materials, but rather the
bicycle frames made of them. Do you find your terms 'ring' and 'thunk' to be
adequate to connote transmit 'high' frequency vibrations to the rider in
different ways? I don't. Most people use 'ring' in reference to vibrations
as a word to describe an audible, not tactile, experience. I bet your test
for a bike frame's ability to 'ring' performed while not riding it is to
somehow tap it and listen. I call bullshit, prove me wrong.
>I just like the way steel rings beneath me on a good bike.
Nobody is trying to take that away from you. Help us explain the 'harsh'
phenomenon now.
-Brian
--
DEMPSEY,BRIAN DAVID
Georgia Institute of Technology, Atlanta Georgia, 30332
Mark Hickey
dbl...@phy.ucsf.eduDELETETHISPART writes...
>
>mhi...@cynetfl.com says...
>>Luckily, even a high pressure tire does a pretty good
>>job of damping (not dampening) out these impacts, but still,
>>a component of this "noise" is going to make it through the
>>tire to the rim.
>
>The tire is going to be a low-pass filter, and the
>higher frequencies are hardly going to be transmitted.
>If you want to feel those high frequencies better ride
>a rim with no tire.
Which is what I said (or meant to say, at least). I agree
that the vast majority of this "acoustic energy" is going to
be absorbed in the tire's sidewall - but not all... whether
the amount that is passed along is enough to make a difference
is the question. At the very least, there will be some acoustic
coupling through the dense air inside the tire to the rim.
>The ability of the human skin to sense vibrations with
>frequencies in excess of 500 Hz is extremely limited.
>The highest frequency receptors in the body are Pacinian
>corpuscles and their frequency tuning is a U shaped
>curve with maximal sensitivity around 260 Hz - at
>which point they are sensitive to vibrations close
>to a micron in size. There is a steady rolloff from there.
>
>I have extensive experience in studying percepts that are
>based on Pacinian corpuscle, and I do not think they are
>well activated in cycling no matter what the frame
>is made of.
Interesting, though. What would be the end effect of
a 260 Hz vibration of low amplitude getting through to
these corpuscles? Anything that could be described as
"tiring"?
>If there were even significant high frequencies being
>passed to the rider there would be significant
>occurrences of tendinitis.
Seems that there would be room for "less-than-significant"
amounts of the vibration getting through. If large amounts
would cause tendinitis, it follows that small amounts would
cause discomfort at least.
Note to the gentle readers - I'm not a doctor, I don't play
one on TV and if I ever took biology in High School, I don't
remember it. I went to school in the 70's....
>But more to the point the tire is simply not going
>to pass much high frequency vibrations. The pneumatic
>tire is a low pass filter which is why it is so
>comfortable compared to a solid tire.
I would postulate that the difference in bike frames would
be very pronounced if you were running solid tires. Of course,
the range would be from "unbearable" to "really unbearable".
>>Too bad we don't have someone in this newsgroup with access
>>to lots of the really expensive test equipment that would be
>>required to test this hypothesis - that is, someone who works
>>for a company that manufactures high quality electronic test
>>equipment - like HP for example....
>
>The real problem is not that the equipment is not accessible,
>but that the person who runs the equipment generally has
>more important things to do.
But we're talking about the holy grail of cycling here. The
discovery of the promised land. Perpetual motion, the end of
hunger.
Or, at least the end of a long, tired thread on r.b.t.
Mark Hickey
Habanero Cycles
http://www.cynetfl.com/habanero/
Home of the $675 acoustically tuned ti frame
Matt O'Toole
Drew Eckhardt <dr...@qualcomm.com> wrote in article
<5s7qg5$h...@qualcomm.com>...
> Until some one (any one from the big companies, or publications
listening?)
> gets one or more frame builders to throw together identical TIG welded
> frames made from the different metals (titanium, aluminium, oversize
steel),
> paints them identically, builds them with identical components, and does
a
> double-blind comparison, it's silly to decide that people are
experiencing
> a placebo effect, or that aluminum frames are actually harsh.
Apparantly, it's been done:
da...@erinet.com wrote in article <3408ec6f...@nntp.erinet.com>...
> Try to find a copy of the December, 1996 issue of _Bicycle Guide_
> magazine. In that issue, the editors tested 7 Italian frames built by
> Antonio Mondonico. The frames were identical in all respects, except
> that they were built with Aelle, Cromor, Thron, Brain, SLX, Neuron and
> EL-OS tubesets from Columbus. Each bike was the same size and equipped
> with the same components. The bikes were "numbered" but otherwise
> were not distinquishable. This is about as close to a "blind test" as
> you'll get on bicycles.
> And the results? The bikes were just about identical. To quote the
> article " . . . the personality of a bike is determined much more by
> fit, frame geometry and components than by what kind of tubing lies
> under the paint."
Yet, that same publisher continues to print bike reviews that go on and on
about frame compliance and road feel. In a recent article, the reviewer
said that since he weighed only 145 lb., he didn't normally like aluminum
bikes, because they "beat him up." By this, he implies that in contrast to
bikes made of other materials, aluminum bikes don't flex enough in the
vertical direction, at least under his light weight.
Matt O.
Trad...@rocketmail.com
In article <5sv4nh$fk1$1...@newbabylon.rs.itd.umich.edu>,
jget...@compuserve.com wrote:
> In <Pine.ULT.3.96.97081...@ivy.cs.unca.edu>, boyd
<bo...@cs.unca.edu> writes:
> >And anyone who has ridden a loaded touring bike would agree with Mark H.
> >The supension (tires) is much more effective at isolating the rider when
> >there is a lot of mass in, or mounted on, the frame.
John said:
> For the same effect you could just unload the bike and let some air out of
>your tires ;-)
This would give equal tire drop to a loaded bike,
(Tire drop is the difference between the loaded rolling
radius of the tire, and its unloaded radius. A good rule
of thumb is to aim for a drop equal to 15% of the tire's
height above the rim. If drop is over 15% at max pressure,
get a wider tire. Credit Frank Berto and Michelin for this.)
but I believe the main benefit of loaded panniers
is in their suspended nature. The contents of
panniers are not rigidly attached to the bike frame,
so they bounce around a lot. The energy which causes
this bouncing comes from bike motion, of course, so
there is a corresponding reduction in the energy
available to jackhammer the saddle into your buttocks. :()
Mick.
-------------------==== Posted via Deja News ====-----------------------
http://www.dejanews.com/ Search, Read, Post to Usenet
Matt O'Toole
Dave Blake <dbl...@phy.ucsf.eduDELETETHISPART> wrote in article
<5sv7kc$15...@itssrv1.ucsf.edu>...
> The real problem is not that the equipment is not accessible,
> but that the person who runs the equipment generally has
> more important things to do.
I'm sure there's an engineer-tinkerer-cyclist out there who would be
interested, and perhaps could be enticed with a free frame, some cheap
parts, etc. Even a byline in a magazine would be enough for some people,
but I doubt the bike press would be interested. With their favorite line
of bull debunked, what would they write about?
> But to address the question in the header, Cannondale
> is the only reason. Steep geometry and really oversize
> tubing.
If vertical frame flex is insignificant, so how could the bigger tubes of
the Cannondale make a difference? Would their compliance be less
insignificant?
I agree with you on the steep geometry, though.
I still think auditory resonance is what influences most peoples'
impressions of ride quality. What we may need is a deaf test rider!
Matt O.
Trad...@rocketmail.com
In article <01bca74f$73f62f20$2aca...@Pmatt.deltanet.com>,
> > I now believe the difference, if there was one, to be in the lighter
> > weight of the Klein.
> Now you're swimming in dangerous waters.
I presented it as opinion, and it agrees with Klein's
very technical analysis of the situation. (Read Klein
catalog 20 times before my roomate bought said bike.
Maybe preconceived notion rule applies:))
Mick:
> > Gary Klein "discovered" this concept in an engineering class,
> > (it's taught to everybody) and patented the concept. (gov't
> > stupidity at work :)
Matt:
> I believe Klein's patent has to do with the rigidity of the frame, not the
> weight.
The patent GK got in the late 80's was for any frame lighter than X and
stiffer than Y. It had to have both the weight and stiffness features to
violate the patent, and construction materials were not a factor. If
someone made a light, stiff frame out of balsa wood, he would have been
sued by GK under this patent. It was based on his claim that before he
came along, everyone thought that stiff frames rode poorly. His
innovation was to show that heavy frames rode poorly. The stiffness of a
steel frame with 1 1/8" tubes is proportional to the weight of the
tubeset, so people just guessed that stiff frames rode poorly because
they were stiff. I still think it's stupid to give out a patent for
someone who applies common engineering principles to a new situation, but
GK DID start the frame revolution of the 80's, IMO. BTW, as I recall,
GK's suit against Cannandale died when Roger Durham (of Bullseye fame)
showed up in court with an oversize aluminum frame which he made before
GK made his. (Roger's frame was a custom made beater bike for his niece
to take to college! Wish he was my uncle. :) ) I don't know about any
other patents GK may hold.
Mick:> > 3. Sound, less being better.
Matt:
> I think this is the key to this whole fiasco. Again, however, it has
> nothing to do with mass. (Didn't you just say that lighter bikes ride
> smoother, anyway?) An aluminum bike's large tubes resonate loudly,
> compared to the small tubes of a steel bike. Therefore, every rattle,
> squeak, and pop on an aluminum bike is heard. With so much noise going on,
> a rider may think it's because the bike is riding more harshly, and causing
> more things to rattle.
Just one point to make. I said light=smooth. I did not say a 12yr old
Cannonball was light or smooth. Some cheap ones went close to 24lbs.,
and the framesets around 6lbs. (My ride at the time was 6 3/4lbs of heavy
gauge Columbus SP, built into a 21lb bike. It rode better than a friend's
early 'dale, but he may have had narrower tires, can't remember for sure.)
Mick:> > 4. Wheelbase, less being worse.
Matt:
> If you think about it, the differences in chainstay dimension are very
> small, and the resulting difference in vertical motion is even smaller.
> You may be correct about the rocking motions with respect to wheelbase.
> However, the difference in wheelbase between various bikes seems
> insignificant to me compared to the much wider variation in rider sizes.
Never said it was significant. Just tried to cover all the bases:)
Mick:
> > 5. Damping. On a metal frame,
> > the paint damps more than the frame. This goes for Al, Ti, Steel,
> > and beryllium. With composite frames, the damping is not
> > significant when compared to the tires.
Matt:
> The flex isn't significant with any of these, so the damping isn't, either.
I see your point, but we both agree that frames resonate and produce
sound. damping would be a factor if there was much of it. (maybe a rubber
coated frame would ride better:)
> > 6. Vertical flex in any frame (even my 1987 Look, or the 979 Vitus
> > I almost bought) is small compared to tire compression.
> > (See numberous posts in this group)
>
> The word is "insignificant."
Of course. Looks like we agree on everything but the weight issue,
and I've got the amazing Rich on my side there.
pp00...@mindspring.com
Brian Dempsey concocted a ludicrous response referring to my use of
the term "tone" which I used to describe the general tack of his
responses in this thread. Unfortunately, I lost my connection when
responding, so his own words are not cited in my rebuttal which
follows:
Brian,
You know precisely what I meant by "tone". Had I been referring to
"muscle", I would have used the word "muscle" in conjunction with
the word "head" ... "muscle head"! From your inane banter, it has
become blatantly obvious that semantic obfuscation is the underlying
theme of your responses. Seduced by the intoxicating cacophony of
his own incessant, banal, drivel ..... Brian babbles on ..... - Jim
McNamara
da...@erinet.com
On 14 Aug 1997 13:33:09 GMT, mhi...@cynetfl.com (Mark Hickey) wrote:
>da...@erinet.com writes...
>>
>
>>BTW, the _frame_ weight of the tested bicycles ranged from 220g
>>(EL-OS and Neuron) to 300g (Thron and Aelle).
>
>Wow... I never realized my frames were so much heavier than
>steel.... ;-)
Mark:
I misspoke. Those were the tubeset weights for the top tube
only. From another table in the article, the frame only weights were:
Aelle 4lb 12oz
Cromor 4lb 7oz
Thron 4lb 12oz
Brain 4lb 8oz
SLX 4lb 8oz
Neuron 4lb 0oz
EL-OS 4lb 0oz
The fork weights ranged from 1lb 6oz (SLX!) to 1lb 9oz (Aelle).
Strangely enough, the EL-OS fork weighed in at 1lb 8 oz, cancelling
out some of the benefit that you paid for in the lightweight frame
tubes.
One other observation from all of this is that the weight of the lugs
and brazing material are significant -- largely overshadowing the
actual weight of the tubesets.
.................dh
boyd
On 14 Aug 1997, John Getsoian wrote:
> In <Pine.ULT.3.96.97081...@ivy.cs.unca.edu>, boyd <bo...@cs.unca.edu> writes:
>
>
> >And anyone who has ridden a loaded touring bike would agree with Mark H.
> >The supension (tires) is much more effective at isolating the rider when
> >there is a lot of mass in, or mounted on, the frame.
> >
> For the same effect you could just unload the bike and let some air out of your tires ;-)
>
> -regards
> John Getsoian
> [jget...@compuserve.com
> or sls...@umich.edu]
>
Have you tried it? It doesn't work that way. Something about the tires
having to support the weight of the rider as well as the frame...
Mark
Mark Hickey
da...@erinet.com writes...
>
>BTW, the _frame_ weight of the tested bicycles ranged from 220g
>(EL-OS and Neuron) to 300g (Thron and Aelle).
Wow... I never realized my frames were so much heavier than
steel.... ;-)
FWIW, here's my pet theory on the difference in ride quality
between different materials....
An asphalt road is a bumpy thing - comprised of literally
millions of 1-3mm "bumps". Cruising over these at 20mph
(35kph) causes your high-pressure tire to impact these little
bumps at a random rate measured in hundreds to thousands per
second, squarely in the "audio" range. If you were to plot
this on a spectrum analyzer, it would look like a broadband
noise, centered around 1000-2000 cycles per second, with
components of the noise extending well above and below that
level, due to the random nature of the distribution of the
"bumps".
Luckily, even a high pressure tire does a pretty good
job of damping (not dampening) out these impacts, but still,
a component of this "noise" is going to make it through the
tire to the rim. At this point, it's going to be transfered
through the spokes (which should do a dandy job of transmitting
it) to the hub. Some more "decoupling" is going to occur there,
but still, some will reach the fork and the rear dropouts. If
this were true, there would be a noticable difference in "feel"
between a steel fork and a carbon fiber fork - and there are
few who have ridden both who would argue that this is the case.
Anyway, once these low amplitude, high frequency vibrations
reach the frame, the frame's ability to damp or pass these
frequencies will come into play. It's hard to say what the
human butt "likes to feel", but it seems that total damping
isn't optimum for most folks, as evidenced by the fact most
folks prefer the "feel" of steel and ti over carbon fiber,
which has the highest damping of all.
Since the "frequency response" of all the individual components
will determine how the entire bicycle "system" passes vibrations
from the road to the rider, it's impossible to say how any one
particular bike will fare - if the individual components have a
"resonant frequency" (that is, one frequency that they will
pass mechanically very efficiently, much as a bell), that is
similar, the overall "feel" will be correspondingly impacted.
If, OTOH, the frame doesn't efficiently pass the "resonant
frequency" of the wheel (or components thereof), there will
be less of this high frequency energy reaching the rider.
Too bad we don't have someone in this newsgroup with access
to lots of the really expensive test equipment that would be
required to test this hypothesis - that is, someone who works
for a company that manufactures high quality electronic test
equipment - like HP for example....
<insert detached whistling here>
Mark Hickey
Habanero Cycles
http://www.cynetfl.com/habanero/
Home of the $675 ti frame
DEMPSEY
hau...@mbi.org writes:
>In article <5sou5h$d...@acmez.gatech.edu> ch8...@prism.gatech.edu (DEMPSEY) writes:
>>From: ch8...@prism.gatech.edu (DEMPSEY)
>>Subject: Re: Why do people think Alu frames are HARSHER? / One for Jobst ! / Tom K.
>>Date: 12 Aug 1997 02:00:17 -0400
>DEMPSEY wrote:
>>Stepping stone? What does 'stepping stone' mean metallurgically? Do you
>>know what you're talking about here? You sound like a bike salesman!
hau...@mbi.org wrote:
>How so?? Although I've already provided an implied meaning of 'stepping
>stone', I meant that it is (about halfway) between aluminum and steel, in
>terms of stiffness to weight, strength to weight, and mass.
As metals, aluminum, tianium, and steel all have similar specific rigidity,
or, 'stiffness to weight.' Speaking of the 'mass' of one metal being between
two others makes no sense. Your 'stepping stone' explanation seemed like
one of a bike salesman for that type of metallurgical information.
DEMPSEY wrote:
>>What is the relationship between comfort and mass, as you understand it?
>>Are you more 'comfortable' in the knowledge than you own a lightweight
bicycle
>>than you would be owning a heavier one? I don't get it.
hau...@mbi.org wrote:
>That's clear enough. A lighter frame (and bike) will better conform to road
>surface. Thus, it's more comfortable.
That one is not clear to me, either. It sounds like more bike sales-speak.
DEMPSEY wrote:
>>What value of the variable 'frame fitting the rider' yields the most comfort?
>>I'd bet a one-size-fits-you recumbent is more comfortable to coast along on
>>than some Cannondale 'Criterium' road frame that you'd say was a good fit for
>>a particular rider.
hau...@mbi.org wrote:
>Recumbents? Now you're using Jobst's trick - changing the subject simply to
>start an argument.
My subject remained the same: ride comfort or quality as a result of different
bicycle frames. We can limit the discussion to 'upright' frames, my point
was that 'frame fitting the rider' was not the answer to the question at
hand regarding why some frames produce bikes whose ride quality is described
as 'harsh.'
hau...@mbi.org wrote:
>Brian, what exactly is your point? You apparently want to argue, but don't
>know what to argue about.
>Rich
Rich, we've been arguing about what makes a bicycle built around some par-
ticular frames be described as having a 'harsh' ride, that's right in the
subject line. Many things have been proposed, but nothing solid other than
psychology has been suggested. Many of us don't want to believe that, because
we think we're really feeling something. If you have something in addition to
what you've offerred so far as explanation for this phenomenon, I'm sure that
I'm not the only one who'd like to hear it. Make it something harder to
discredit than what you have offerred so far, though, even if it's complete
'fabrication.' It'd probably be a while before anyone would test to verify
or discredit you, and in the meantime a lot of sore muscles could be assuaged
by some soothed minds.
DEMPSEY
Tom Kuncih wrote:
>Uh, maybe if you put the two bikes next to each other and measure
>the differences you will begin to see why they fell different. In
>any case, comparing a perfect, expensive, well though out bike
>like
>the Merlin with a mass produced upper-middle class bike like the
>Centurion is ....(unfair)
>Why not compare your Merlin with a Master Light?
DEMPSEY wrote:
>> Why does the production volume difference between these two bicycle frames
>> invlaidate the comparison of two bicycles built around them?
>> Does the prestige of ownership affect the ride quality of a bicycle?
>> I don't think that you meant to say that it did, so what WERE you trying
>> to say? You seem convinced that a Centurion, or other less prestigious
>> brand of bicycle, could certainly not be as pleasurable to ride as something
>> like a Merlin. How do you know that what you call 'well thought out' is
>> not, in fact, merely, 'well differentiated from the commonplace?'
Jim wrote:
>Brian,
>Please note that your reply was directed to two different authors
>Being one of them, I will address that portion which was directed my
>way. Contrary to what you assume, I do not contend that a less
>prestigious brand of bicycle, by default is necessarily less
>pleasurable to ride, but I do stand by my contention that my
>Centurion Ironman was unequivocally less pleasurable to ride that my
>Spectrum titanium bike.
Jim, My reply was to Tom's offerring, you may have simply been sent a copy.
It was Tom who seemed to make that contention that prestige had something to
do with a bike's ride, Jim, never mind.
He assigned 'classes' to your two bikes and stated that it was not fair to
compare bikes of two different 'classes.'
I didn't agree that bikes of one of Tom's 'lower classes' should ride worse
somehow that one of his 'upper classes' simply as a result of these 'class-
ifications' or of teir production volumes.
I'm not challenging that you like your Merlin or Spectrum better for it's
ride, Jim. I'd like it better, too.
Jim wrote:
>There is little point in engaging in a
>debate over an issue which has subsequently been resolved
>experientially. Just for the record, however, I am quite
>comnfortable with prestige of ownership (curb appeal), but I also
>realize that expense does not equate to ride quality. As concerns
>"well thought out" and "well differentiated from the commonplace",
>these are certainly not mutually exclusive categories. Suffice it
>to say that when something works well, that this is generally
>attributable to something having been well thought out, and in this
>particular example, "well differentiated from the commonplace" also
>happens to apply.
IHey Jim, I think that some involved here are interested particularly in why
it is that 'well differentiated from the commonplace,' 'well thought out,'
and an improved ride quality over your Centurion are three coincidental traits
of your Spectrum. Tom seemed to say that these things coincided as a natural
result of the two bikes being of different 'classes' and he noted that they
were produced in different volumes. This is not a rare opinion among
bike lovers, but I asked how Tom could know that the coincidence of these three
traits being applicable to your Spectrum was one to be expected.
Here's an example:
I can't imagine that many people today would be very happy riding their new
'old stock' Exxon Graftek, yet while we could all have fun pointing out,
here in 1997, things about it that we consider 'not well thought out,' it was
more commonly the opinion, circa 1978 (after a 1976 and 1977 national road
championship under their team) that the Exxon Graftek was at LEAST 'well
thought out,' if not downright excellent. Making a statement, in 1978, that
somparing someone's 'well tought out' Exxon Graftek to their previous
'mass-produced upper-middle class' Nishiki was 'unfair' would do NOTHING to
help explain why one bike rode better than another. I'm in no way demaning
your Spectrum, but we have yet to see something really good offerred as an
explanation of why one frame produces a bike that rides 'harsher' than one
which another frame produces.
Jim wrote:
>- I suspect from your tone, that you too consider
>yourself "well differentiated from the commonplace". Brian you're a
>legend in your own mind! - Jim McNamra.
My tone?
I don't understand HOW can assess my muscle condition based simply upon
what I've typed here, or were you somehow picking up my voice? I don't
know how you've assessed me as having legendary tone. At any rate, I'll
be a legend in YOUR mind soon enough...
Matt O'Toole
da...@erinet.com wrote in article <3408ec6f...@nntp.erinet.com>...
> Try to find a copy of the December, 1996 issue of _Bicycle Guide_
> magazine. In that issue, the editors tested 7 Italian frames built by
> Antonio Mondonico. The frames were identical in all respects, except
> that they were built with Aelle, Cromor, Thron, Brain, SLX, Neuron and
> EL-OS tubesets from Columbus. Each bike was the same size and equipped
> with the same components. The bikes were "numbered" but otherwise
> were not distinquishable. This is about as close to a "blind test" as
> you'll get on bicycles.
> And the results? The bikes were just about identical. To quote the
> article " . . . the personality of a bike is determined much more by
> fit, frame geometry and components than by what kind of tubing lies
> under the paint."
So, why do the editors of that magazine (or its successor) continue to
ramble on about frame compliance in their bike reviews? Have they decided
that bullshit sells so well that they can't afford not to print it?
Matt O.
DEMPSEY
A factor determining ride comfort or quality was proposed...
>>> 1. Preconceived notions. Research in judgement and decision making
>>> has shown that when you get an idea in your head, it tends to stay
>>> there. Corollary: if the media tells you a bike rides rough, it
>>> will ride rough. I had the fortune of riding an early production
>>> Klein (1984 touring Performance) before the media attacked C-dale,
>>> and thought it a little smoother than my steel touring bike.
Someone else added...
>>I'm glad you used the word "preconceived." It is true that ride quality is
>>often thought, not felt.
jo...@WOLFENET.COM wrote:
>Before the anti-Cannondale movement, most people I talked to
>"knew" that aluminum frames were "soft" and "noodly" because the
>common aluminum bikes were Alans and Vituses, not Cannondales and
>Kleins. They misattributed the flex to the material rather than
>the overall frame design and materials combined.
But did they call them 'harsh' riding? I've never heard them being called
such things, although I have heard 'smooth' as describing their ride quality.
Do you think that bikes described as 'soft' and 'noodly' are never also
described as 'harsh?' Can we find all the 'harsh' ones and see what attribute
they all share that makes them so?
I've owned a fair assortment of bikes, two of them were narrow-tired Cannondale
bikes, of vintages '86 and '96. I never tried to resolve the comfort problems
my butt had on those two bicycles, enjoying them for what little I found them
to be good for, then got rid of them. I can understand when people attribute
those bikes a 'harsh' ride, and in my own experience there are many similarly-
equipped, similar-geometried, similarly-'fitting' bikes which have not caused
me the comfort problems the Cannondales did. I, like many of the others, don't
want to agree that the ride comfort difference is only psychological, but
nobody has produced anything solid as explanation yet.
The other 3 factors offerred as ride comfort issues have problems.
Let's hear some more ideas, and less drivel about the old ones.
DEMPSEY
Tom Kunich wrote:
Jim McNamara wrote:
Tom Kunich wrote:
-Brian
Ed Chait
Dave Blake wrote:
>
(much snippage)
>
> But more to the point the tire is simply not going
> to pass much high frequency vibrations. The pneumatic
> tire is a low pass filter which is why it is so
> comfortable compared to a solid tire.
>
> ...
Ok, so if it's not a question of high frequencies, then perhaps it could
be a question of amplitude? Another poster mentioned that Kestrel had
charts demonstrating that a carbon fiber frame was excited much less by
vibration than other materials. Perhaps aluminum frames don't dampen
vibration very well.
Unfortunately, my friend with the Kestrel won't let me ride it. I was
trying to convince him to let me mount my wheels and saddle on it and
take it for a spin, but he seemed to become quite suspicious of the
whole thing:).
Ed Chait