Rolf Vector Pro or other wheelset?
Bernie Yee
ragging on VPs in this NG awhile back.
Any thought as to durability of these wheelsets as racing tubulars? I weigh
about 160, more of a sprinter than a climber (hah! understatement), and was
looking to MAYBE replace my Fir Isidis (like the old Mavic GL 330)/DA racing
tubulars with something new and snazzy.
Still thinking of riding with a front Spinergy though.
TC
3 years. I have done about fifty cat.4 races in the past 30 months. I
have ridden/raced most exotic wheelset that are available to general
public; Specialized Tir-spoke, Corima 4-spoke, Zipp 340/Cane Creek,
Mavic Tri-spoke, Heliums, GL 280's, GL 330's, Cosmic Carbone, HED CX,
DEEP, Rolf VP and the new D/A 7700 wheelset.
Each wheelset offer different benefits, but as a better than average
climber/sprinter, I find myself liking the D/A 7700 wheelset more than
others, maybe I perfer them for the TTs as well.
To me, it make sense that without the nipples at the rim, the wheel does
accelerate faster under me, requires less power to rotate that wheel
from a standstill or keep them rotating at speed, it may decelerate
faster once out of power, but so far I am happy with its performance.
TC
TC
3 years. I have done about fifty cat.4 races in the past 30 months. I
have ridden/raced most exotic wheelset that are available to general
public; Specialized Tir-spoke, Corima 4-spoke, Zipp 340/Cane Creek,
Mavic Tri-spoke, Heliums, GL 280's, GL 330's, Cosmic Carbone, HED CX,
for over 100 miles each, some of them more than 1000 miles.
climber/sprinter, I find myself liking the D/A 7700 wheelset more than
others, maybe I perfer them for the TTs as well.
To me, it make sense that without the nipples at the rim, the wheel does
accelerate faster under me, requires less power to rotate that wheel
from a standstill or keep them rotating at speed, it may decelerate
faster once out of power, but so far I am happy with its performance
Mark McMaster
>
> I weight 130 lb., been riding about 10-13,000 miles a year for the past
> 3 years. I have done about fifty cat.4 races in the past 30 months. I
> have ridden/raced most exotic wheelset that are available to general
> public; Specialized Tir-spoke, Corima 4-spoke, Zipp 340/Cane Creek,
> Mavic Tri-spoke, Heliums, GL 280's, GL 330's, Cosmic Carbone, HED CX,
> DEEP, Rolf VP and the new D/A 7700 wheelset, I have ridden most of them
> for over 100 miles each, some of them more than 1000 miles.
> Each wheelset offer different benefits, but as a better than average
> climber/sprinter, I find myself liking the D/A 7700 wheelset more than
> others, maybe I perfer them for the TTs as well.
> To me, it make sense that without the nipples at the rim, the wheel does
> accelerate faster under me, requires less power to rotate that wheel
> from a standstill or keep them rotating at speed, it may decelerate
> faster once out of power, but so far I am happy with its performance
> more than any other wheelset that have tried.
It might make sense to you to put the nipples at the hub,
but that doesn't mean that it really makes any difference.
Just how much do you think a nipple weighs? An aluminum
nipple weighs about 0.3 gram, and even a "heavy" brass
nipple only weighs about 0.9 grams. 16 nipples on the rim
is about 15 grams, which, when you compare it to the 68,000
grams of the rider and bike, doesn't mean diddly squat.
Besides, sometimes moving the nipples to the hubs to try to
reduce moment of inertia backfires. Cane Creek wheels also
put the nipples at the hub, and in test of a group of
aerowheels they had the highest moment of inertia.
Mark McMaster
MMc...@ix.netcom.com
TC
plus spokes.
Once again, do you have anything to share for your experience in riding
different kind of aero wheels? if so, share them, if not, shut up.
Jon Isaacs
>plus spokes.
Do you really think you can detect the difference in 15 grams of nipple mass in
the accelleration of the bike? This is the equivelent of being able to detect
a difference of 1 oz of water in your water bottle or 1 oz of body weigtht. I
would suggest that in a blind test, there is no one who could make this
distinction.
>Once again, do you have anything to share for your experience in riding
>different kind of aero wheels? if so, share them, if not, shut up.
You have provided your impression of these wheels, however you have not
provided any data or real information. A bit of research on the aerodynamics
of wheels and mass of the wheels will show that small differences in mass is
quite unimportant, wheels are governed by aerodynamics under racing conditions.
So, rather than telling someone to shut up, try to use your noggin like the
rest of us and figure out how much changing the position of the nipples could
really effect the performance of the wheel. Consider that individual tires and
rims for that matter of a specific type vary in mass significantly more that
the mass of the nipples. Then consider the total mass of the spokes. Then
look at the aerodynamic drag losses.
Now try to convince someone that changing the nipple position can make a
measureable difference.
jon isaacs
Qui si parla Campagnolo
accelerate faster under me, requires less power to rotate that wheel
from a standstill or keep them rotating at speed, >>
Don't forget the steel inserts in the rim to hold the spokes, they weigh more
than brass nipps and the energy required to accelerate from a stop is dependent
on the mass of bike and rider. Where the weight is on the rim means nada-
Peter Chisholm
"Vecchio's" Bicicletteria
1833 Pearl ST.
Boulder, CO
(303)440-3535
http://www.vecchios.com
Qui si parla Campagnolo
<< was
looking to MAYBE replace my Fir Isidis (like the old Mavic GL 330)/DA racing
tubulars with something new and snazzy >>
Tough to beat a nice pair of handbuilts, built specifically for you and your
riding needs and requirements, Like the wheels you have-
Ain't snazzy, but will get you to the finish line-
CV2572
>To me, it make sense that without the nipples at the rim, the wheel does
>accelerate faster under me, requires less power to rotate that wheel
>from a standstill or keep them rotating at speed, it may decelerate
>faster once out of power, but so far I am happy with its performance.
Here we go .....
Robin Hubert
Mark Hickey
>Don't forget each nipple needs spoke to connect to, weight of nipples
>plus spokes.
Yeah, I'm sure Mark McM never thought of that.
>Once again, do you have anything to share for your experience in riding
>different kind of aero wheels? if so, share them, if not, shut up.
Interesting attitude. Perhaps you can tell us all how we can
accurately test wheels by riding them. How we can eliminate the
dozens of variables (wind speed and direction, physical condition at
that instant, etc.) to strain out the tiny differences between wheels.
Why is it that so many people insist that the laws of physics can be
overcome by "real riders"?
Mark Hickey
Habanero Cycles
http://www.cynetfl.com/habanero/
Home of the $695 ti frame
TC
Can you offer any proof that the energy required to accelerate 15gm. of
spokes and nipples on a wheel is insignificant?
Can you offer any experience in riding any aero wheelsets?
I am convinced that changing the position of the nipples makes a
difference because I have ridden them, I have pedaled my bike with these
wheels, raced with these wheels, climbed with these wheels.
Have you done all that and come to your conclusion?
Provide answers or experiences according to the topic, please.
TC
Jm1226
>if so, share them, if not, shut up.
Shut up. No you Shut up. I'm not going to shut up, you shut up. I'll make you
shut up. Not if I make you shut up first.
Kinda takes you back to the third grade doesn't it. :-> But then again when I
was in the third grade we weren't arguing about something as important as the
position of a nipple.
John
"Everyday for us something new
Open mind for a different view
And nothing else matters" Metallica 1991
Bernie Yee
all the input on this thread. My existing wheels are sweet, but I was
looking for some reason to justify spending more money. Heh.
I'll bet a pair of Heliums roll faster than my existing tubulars... but less
spokes gotta mean less durable.
And the Rolfs (and Shimano DA wheels) look pretty cool.
"Jm1226" <jm1...@aol.com> wrote in message
news:20000716180003...@ng-fo1.aol.com...
TC
aero wheelsets so far?
Does anyone else have experience with riding other aero wheelsets to
share?
I posted my thoughts on riding different wheelsets according to the
topic of this thread, I don't appreciate people attacking me without
offering any personal experience of actually riding these different
wheelsets.
TC
Mark McMaster
>
> Don't forget each nipple needs spoke to connect to, weight of nipples
> plus spokes.
Both wheels use the same type of spokes, so there is no gain
or loss in the spokes themselves.
> Once again, do you have anything to share for your experience in riding
> different kind of aero wheels? if so, share them, if not, shut up.
I was simply offering up facts. I forgot to add some
sources of the information:
To see that Cane Creek wheels, which haver their nipples at
the hub instead of the rim, actually have a higher moment of
inertia, see:
http://www.damonrinard.com/wheel/grignon.htm
To see that Shimano's wheels, with their spokes attached to
the sides of the rim, have pathetic lateral stiffness, see:
http://www.damonrinard.com/wheel/index.htm
So apparantly, you want people with actual facts to shut up,
so that all decisions can be made on highly subjective and
impressionable opinion? You are truly a marketing person's
dream.
Mark McMaster
MMc...@ix.netcom.com
Mark McMaster
>
> Jon,
> Can you offer any proof that the energy required to accelerate 15gm. of
> spokes and nipples on a wheel is insignificant?
According to the laws of motion, the moment of rotational
inertia of a mass is equal to it's mass times it's radius
squared: I = M*R^2.
Because the wheels rotate in direct proportion to the speed
of the bicycle, the effective linear inertia of mass at the
peripheral of a wheel is equal to the actual mass plus the
rotational inertia over the radius squared:
M(eff.) = M + I/(R^2) = M + (M*R^2)/(R^2) = M + M = 2*M
Therefore, the effective inertia of 15 grams at the rim is
30 grams. Compared to the 68,000 grams of the bicycle plus
rider (130 lb rider + 20 lb. bike), the change in the
effective inertia of 15 grams at the rim is 0.044 percent
(that's one part out of 2270). The effective of removing 15
grams from your rim is less than half the effect of removing
a Powerbar from your back pocket (65 grams).
> Can you offer any experience in riding any aero wheelsets?
I have ridden several sets of aerowheels, with from 12 to 20
spokes, and rims from 25mm to 42mm deep. Except for perhaps
sounding a little different, and some providing better
braking than others (depending on what the sidewalls are
made of), I can't really tell any difference.
> I am convinced that changing the position of the nipples makes a
> difference because I have ridden them, I have pedaled my bike with these
> wheels, raced with these wheels, climbed with these wheels.
> Have you done all that and come to your conclusion?
Based primarily on a knowledge of the laws of physics, and
partially from personal experience, I am positive that you
can not tell the difference between where the nipples are
placed, and you are only fooling yourself if you believe
that you can.
Mark McMaster
MMc...@ix.netcom.com
Mark McMaster
"Feelings" or other subjective judgment is a poor criteria
for selecting racing equipment. Racing is a very objective
enterprise - the winner is the one who finishes the course
first. The winner is the is the rider who _is_ the fastest,
not the one who _feels_ the fastest.
This is a technical forum. Assertions presented without
supporting evidence are subject to challenge. To counter a
challenge with "Shut up" strongly implies that can't
substantiate your claims.
Mark McMaster
MMc...@ix.netcom.com
Bob Mitke
>To see that Shimano's wheels, with their spokes attached to
>the sides of the rim, have pathetic lateral stiffness, see:
>http://www.damonrinard.com/wheel/index.htm
>
I don't particularly care for the tone of this discussion. Which
is why I will pose the following questions to Mr. McMaster,
who deems it OK to take the piss out of someone because
they stepped on his toes:
Who cares if Shimano wheels have pathetic lateral stiffness,
since all wheels only experience a "few" pounds of lateral
loading during their usage?
How does lateral stiffness effect cycling performance?
Since you advocate increased/high lateral stiffness,
please share your objective, fact based answers to the
questions I have posed above. Please don't speculate or
make any highly subjective remarks. I will only accept
factual, experimentally acquired data in response.
If you expect that everyone should be held to these
standards you proclaim, then so shall you...
-Bob Mitke
Mark Hickey
Heh heh heh... the troll kicks the dead horse yet again...
Mark Hickey
Habanero Cycles
http://www.cynetfl.com/habanero/
Home of the $695 ti frame
>I don't particularly care for the tone of this discussion. Which
Qui si parla Campagnolo
discussion. >>
Then don't participate-
<< Which
is why I will pose the following questions to Mr. McMaster,
who deems it OK to take the piss out of someone because
they stepped on his toes: >>
McMaster wrote a really great piece as to why the weight at the rim meant
nada-(M(eff)=M+I/R^2)=M+(M*R^2)/R^2)=M=M-2*M) or some such thing.
Don't think it's stepping on any toes but actually explaining how weight at the
rim means less than a Powerbar in your pocket.
Jon Isaacs
>spokes gotta mean less durable.
>
Aerodynamic tests indicate that Heliums are identical to a set of 32 hole MA40s
are far as aerodynamic drag is concerned. Their weight is pretty much normal.
The only way they could "roll better" would be if the hubs were better which is
not likely if you have DA hubs or some such.
>And the Rolfs (and Shimano DA wheels) look pretty cool.
Well they may look cool but personally I think that Claudia Shiffler looks a
whole lot nicer. However looks is only where its at if you are Claudia
Shiffler or trying to sell wheels.
For racing check out the aerodynamics, durability and mass of the wheels.
Jon Isaacs
Jon Isaacs
>30 grams.
I would suggest that since this mass is moved from the outer portion of the rim
towards the center that the effect is actually less that 15 grams in rotational
inertia.
jon isaacs
Jon Isaacs
>who deems it OK to take the piss out of someone because
>they stepped on his toes:
If you have been following this thread, Mr. TC has told Mr, McMaster several
times to "Shut Up." This response is the first one where Mark has been less
than totally kind and factual. Clearly he is irriated by Mr. TC's continuing
rude and unpleasent posts directed at Mark.
While I don't necessarily condone Marks response as ideal, it did address the
issues and futhermore was written in a style much less rude than Mr. TC's.
Jon Isaacs
KB
difference with the Shamals. I have zero for 'scientific' data, but I just
didn't feel anything different from my normal riding wheels (which were
pretty nice, mavic freewheel hubs, mavic mach 2 tubulars, conti sprinters).
The trispokes I actually felt like I noticed a difference. Could have been
my imagination, causing me to pedal harder, but thats what I felt, and my TT
times did improve....and they also made that cool noise when shifting
gears.:)
For the record, the Mach 2 wheelset was the toughest of them all. They went
through at least 3 good crashes, as well as several thousand training and
racing miles, including two winters on a cateye indoor trainer. Bombproof!
Built by Colorado Cyclist around 1990.
"TC" <cat...@mail.idt.net> wrote in message
news:39726C...@mail.idt.net...
> Has anyone else offered any of their experience with riding different
> aero wheelsets so far?
> Does anyone else have experience with riding other aero wheelsets to
> share?
> I posted my thoughts on riding different wheelsets according to the
> topic of this thread, I don't appreciate people attacking me without
> offering any personal experience of actually riding these different
> wheelsets.
>
> TC
CV2572
<kbe...@earthlink.net> writes:
>I have ridden on campy shamals and Trispokes. I couldn't 'notice' a
>difference with the Shamals. I have zero for 'scientific' data, but I just
>didn't feel anything different from my normal riding wheels (which were
>pretty nice, mavic freewheel hubs, mavic mach 2 tubulars, conti sprinters).
>The trispokes I actually felt like I noticed a difference. Could have been
>my imagination, causing me to pedal harder, but thats what I felt, and my TT
>times did improve....and they also made that cool noise when shifting
>gears.:)
I don't know about you but, do you ever remember being a kid, and getting a new
pair of (what we used to call) "sneekers"? You know, when I got new sneekers,
I could run faster and jump higher. Need I carry on ...?
Robin Hubert
Jobst Brandt
> To me, it make sense that without the nipples at the rim, the wheel
> does accelerate faster under me, requires less power to rotate that
> wheel from a standstill or keep them rotating at speed, it may
> decelerate faster once out of power, but so far I am happy with its
> performance.
This is an old subject that is based on a bit of misplaced physics.
Although mass ON the periphery of a wheel in contrast to mass on the
frame takes twice as much force to accelerate, it actually makes no
difference because bicycles DON'T accelerate worth a hill of beans and
when they do it, it is primarily in a match sprint or TT on a track...
and it occurs only once in the event.
On the road, what is called accelerating is actually riding away from
the others, initiated at an acceleration that is so small that it
defies measurement on an accelerometer, certainly less than 1/20 g and
only for a moment. At such accelerations, spoke nipples here or there
are insignificant while the mass of the rider and bicycle as a whole
overwhelm any of these differences, and it is differences among
comparable wheels that are under discussion, not the omission of the
entire wheel.
Those who claim to feel these differences are imagining effects from
having bought more esoteric and expensive wheels that must live up to
expectations.
Jobst Brandt <jbr...@hpl.hp.com>
KB
you took a little more time to practice your reading...
Seriously though, is it inconceivable that one would notice a difference at
speed with a set of tri-spokes? I mean, they are proven to be more
aerodynamic than a regular wheel. I'm not talking acceleration, just speed.
Just my opinion....but I see that posting an opinion on this newsgroup seems
to get you in trouble sometimes...
"CV2572" <cv2...@aol.com> wrote in message
news:20000717122411...@nso-cr.aol.com...
cog...@grecc.umaryland.edu
> Has anyone else offered any of their experience with riding different
> aero wheelsets so far?
> Does anyone else have experience with riding other aero wheelsets to
> share?
Let's see, aero wheels that I've used (in semi-historical sequence):
1) shallow Araya aluminun aero rim, 16 bladed spokes (24" front)
2) Unidisc coated lycra wheel cover (rear)
3) CH-Aero plastic disk cover
4) CH-Aero disk wheel (sold by them - same as #3 but glued to rim)
5) shallow Matrix Iso C-Aero rim, 24 bladed spokes
6) Specialized Ultralight (what everybody calls a trispoke)
7) Hed Cx (700C) (front only)
8) Hed Standard disk
9) Hed Cx (650C) built on narrow Hooker hub
10) Campy Vento (front only)
11) Rolf Vector Pros (front and rear)
12) Velocity Deep V built with 18 and 24 bladed spokes F and R
13) Zipp 440 (rear only)
In a blind test (if that were possible), the only difference that I
think I could detect between all these wheels is that some are more
sensitive to crosswinds than others. However, when it comes to speed
(flat or uphill), acceleration, "comfort", "cornering", etc., I can't
tell any difference.
> I posted my thoughts on riding different wheelsets according to the
> topic of this thread, I don't appreciate people attacking me without
> offering any personal experience of actually riding these different
> wheelsets.
People aren't attacking you, only your unsupported (and unsupportable)
assertions. Moreover, you only assume that others haven't any personal
experience with various wheelsets.
--
Andrew Coggan
Sent via Deja.com http://www.deja.com/
Before you buy.
cog...@grecc.umaryland.edu
> Who cares if Shimano wheels have pathetic lateral stiffness,
> since all wheels only experience a "few" pounds of lateral
> loading during their usage?
Lateral loading might be minimal under most conditions, but what if you
clip a pedal and your rear wheel hops sideways? How many pounds of
lateral force do you suppose the rear wheel of our tandem encountered
when we did this in a points race criterium one time?
> How does lateral stiffness effect cycling performance?
See above. Also, a rear wheel with inadequate lateral stiffness may rub
on the brake blocks during high power efforts, esp. climbing.
Note: neither of the above comments should be construed as implying that
the Shimano wheels are not stiff enough laterally. I'm merely pointing
out examples that you overlooked in your haste to stir up trouble.
TC
are traveling at 26 MPH?
If there isn't any significant difference in all the different
wheelsets, why not everyone ride the same old 36 spoke tubulars?
The difference may not be detected when people ride three times a week,
20-40 miles at a time, at paces well within their physical capabilities.
When was the last time you gasp for oxygen that you just can't take in
fast enough? when was the last time you push your heartrate above your
anarobic threashold and keep it there for over 90 seconds?
at those situations, the 15 grams of rotating mass matters more than you
can imagine.
TC
Jobst Brandt wrote:
>
> On the road, what is called accelerating is actually riding away from
> the others,
b...@my-deja.com
TC <cat...@mail.idt.net> wrote:
> Does anyone else actually make an attempt to ride away from others who
> are traveling at 26 MPH?
> If there isn't any significant difference in all the different
> wheelsets, why not everyone ride the same old 36 spoke tubulars?
> The difference may not be detected when people ride three times a
week,
> 20-40 miles at a time, at paces well within their physical
capabilities.
> When was the last time you gasp for oxygen that you just can't take in
> fast enough? when was the last time you push your heartrate above your
> anarobic threashold and keep it there for over 90 seconds?
> at those situations, the 15 grams of rotating mass matters more than
you
> can imagine.
>
> TC
>
faster, then why are you wasting your money and time with shimano dura
ace wheels? Why don't you just sell all those fancy aero wheels that
you've supposedly have/ride and get yourself a set of ADA wheels - 1000
grams for the WHEELSET...think how much faster you can go with a set of
ADAs...you should be able to graduate from cat 4 and be racing for USPS
within the next year or so! The ADA wheels only cost about $3,000 per
wheelset, about what you spend on all your wheels combined. Hey, if
ADAs are good enough for Jan Ullrich, it should be good enough for you.
CV2572
<kbe...@earthlink.net> writes:
>Yes! That is why I said it might have been my imagination. Duh..maybe if
>you took a little more time to practice your reading...
>Seriously though, is it inconceivable that one would notice a difference at
>speed with a set of tri-spokes? I mean, they are proven to be more
>aerodynamic than a regular wheel. I'm not talking acceleration, just speed.
>Just my opinion....but I see that posting an opinion on this newsgroup seems
>to get you in trouble sometimes...
In regards to the last sentence ... yes, that's the whole point of the
forums!!!
Don't forget, criticism ain't all bad.
Robin Hubert
cog...@grecc.umaryland.edu
> Does anyone else actually make an attempt to ride away from others who
> are traveling at 26 MPH?
That's a dumb question. Of course people do - if you're not a sprinter,
and the pack is riding at 26 mph, then you have no choice but to
accelerate to 26+ (i.e., attack) if you want to win the race. And there
are plenty of races that average 26 mph - I suspect that on a flat
course, even the 50+ field at master nationals might go that fast.
> If there isn't any significant difference in all the different
> wheelsets, why not everyone ride the same old 36 spoke tubulars?
Jobstie may not believe that there is a significant difference, but
other people (rightfully do). The question is, what sort of difference?
Compared to "...the same old 26 spoke tubulars...", many modern wheels
are superior from an aerodynamic perspective.
> The difference may not be detected when people ride three times a
week,
> 20-40 miles at a time, at paces well within their physical
capabilities.
> When was the last time you gasp for oxygen that you just can't take in
> fast enough? when was the last time you push your heartrate above your
> anarobic threashold and keep it there for over 90 seconds?
> at those situations, the 15 grams of rotating mass matters more than
you
> can imagine.
Ahh, I see. Your credentials as a Cat. 4 make you uniquely qualified to
feel the difference 15 grams of rotating mass makes.
Andrew Coggan
Mark Hickey
>Does anyone else actually make an attempt to ride away from others who
>are traveling at 26 MPH?
I believe there are one or two of us who do that.
>If there isn't any significant difference in all the different
>wheelsets, why not everyone ride the same old 36 spoke tubulars?
I thought we were talking about the difference in 15g of nipples, not
the difference between a Shamal and a touring wheel.
>The difference may not be detected when people ride three times a week,
>20-40 miles at a time, at paces well within their physical capabilities.
Tell us how you plan to "detect a difference" of 15g on the wheels.
Give us a method of measuring the difference and we'll all report
back.
It's a common position to assume that the faster a rider is, the
better they are at "feeling the subteties". Pro riders are often some
of the most clueless. Besides, Jobst probably has 5x the mileage you
do under his belt (errrr, shorts), and would probably leave you for
dead if you "tried to ride away from him".
>When was the last time you gasp for oxygen that you just can't take in
>fast enough? when was the last time you push your heartrate above your
>anarobic threashold and keep it there for over 90 seconds?
Errrr, most days.
>at those situations, the 15 grams of rotating mass matters more than you
>can imagine.
Actually, it matters a lot less than you imagine (imagine being the
key word). Face it, physics might be boring and unimaginitive, but
they don't call 'em the LAWS of physics because they act differently
if you feel like they should. It's been proven time and time again
that people just can't feel differences of such a small magnitude.
You can either accept that, or assert (as you have been) that the
scientists and the laws of physics are wrong, and you are right.
Mark Hickey
Habanero Cycles
http://www.cynetfl.com/habanero/
Home of the $695 ti frame
>TC
kiwi
> When was the last time you gasp for oxygen that you just can't take in
> fast enough? when was the last time you push your heartrate above your
> anarobic threashold and keep it there for over 90 seconds?
> can imagine.
I guess it's true: There is one born every minute. And
no matter what facts, logic, or reasoning is used in an attempt
to persuade them otherwise, they still Believe.
Makes you want to go out and start a company to make
bogus performance enhacing cycling products; doesn't it?
$700 dollars a pop for a wheelset that is not a lot different
than one that costs $300 has got to provide a very healthy
profit margin.
S Worker
Jobst Brandt wrote in message <8kvc77$4ov$4...@hplms2.hpl.hp.com>...
>
<>SNIP>
>
>Those who claim to feel these differences are imagining effects from
>having bought more esoteric and expensive wheels that must live up to
>expectations.
>
>Jobst Brandt <jbr...@hpl.hp.com>
Jobst and others:
So, what bike and wheel features offer noticable and/or measureable
differences in speed, stability, and comfort?
Steve
Jobst Brandt
> Does anyone else actually make an attempt to ride away from others who
> are traveling at 26 MPH?
Is this a rhetorical question or do you ride alone? Watching someone
pull away, on a casual ride as well as a race, gives the slower rider
the impression of acceleration, when in fact it is not, assuming the
tempo is more than insignificant.
> If there isn't any significant difference in all the different
> wheelsets, why not everyone ride the same old 36 spoke tubulars?
You're using Bob Mitke'isms here. You claim to feel the difference
and on the basis of acceleration, and that is what is not happening.
not that light weight is unimportant or that fewer spokes have less
drag.
> The difference may not be detected when people ride three times a
> week, 20-40 miles at a time, at paces well within their physical
> capabilities.
Low spoke count is measurable on dynamometers and downhill coasting
tests. Bicyclists riding the standing start kilometer on the track
show the advantage on the stop watch. However, someone not performing
a measurable task can most likely not sense these differences although
the wheel may sound different from another wheel.
> When was the last time you gasp for oxygen that you just can't take
> in fast enough? When was the last time you push your heartrate
> above your anarobic threashold and keep it there for over 90
> seconds? at those situations, the 15 grams of rotating mass matters
> more than you can imagine.
You are the one who brought in the word, but imagination is where it's
at, so to speak. Your oxygen uptake, heart rate, and anaerobic stall
is exciting imagery but it only make the probability of perceived
improvement more credible. Under such physical stress, assessing
small differences in inertia is less likely than in a state of rest.
Jobst Brandt <jbr...@hpl.hp.com>
Jon Isaacs
>are traveling at 26 MPH?
Have done one and the same.
>If there isn't any significant difference in all the different
>wheelsets, why not everyone ride the same old 36 spoke tubulars?
There seems to be some confusion. Clearly there are differences in wheels and
some wheels have better/worse aerodynamics than others and, in some situations,
this can make a rider faster.
The real problem I think is that you made the claim that reason that the new
DuraAce wheels were faster was that the nipples were not at the rim but at the
hub.
This claim is easy to refute and I as well as others have done so.
As to whether the DuraAce wheels have aerodynamic superiority, this is
something yet to be established, however any performance differences that may
be felt or measure certainly should not be attributed to moving the spoke
nipples.
jon isaacs
Tim McNamara
<bikes...@aol.comnojunk> wrote:
> Mark McMaster wrote:
>
> >To see that Shimano's wheels, with their spokes attached to
> >the sides of the rim, have pathetic lateral stiffness, see:
> >http://www.damonrinard.com/wheel/index.htm
> >
>
> I don't particularly care for the tone of this discussion. Which
> is why I will pose the following questions to Mr. McMaster,
> who deems it OK to take the piss out of someone because
> they stepped on his toes:
>
> Who cares if Shimano wheels have pathetic lateral stiffness,
> since all wheels only experience a "few" pounds of lateral
> loading during their usage?
>
> How does lateral stiffness effect cycling performance?
>
> Since you advocate increased/high lateral stiffness,
Bob, Bob, Bob. Didn't you ever read that book on logic I recommended?
Your last statement is putting words in Mark's mouth and is, if I
recall the term correctly, an example of sophistry.
This sort of thing is suggestive of a weak position- an argument
lacking in radial and lateral stability as it were. True it up,
improve the bracing angle and try again. ;-)
Tim McNamara
<jbr...@hpl.hp.com> wrote:
> Those who claim to feel these differences are imagining effects from
> having bought more esoteric and expensive wheels that must live up to
> expectations.
An explanation of this can be found in most psychology textbooks under
"cognitive dissonance," although Jobst encapsulates it nicely. Or you
can read the source texts:
Festinger, L. 1957. _A Theory of Cognitive Dissonance._ Stanford CA:
Stanford University Press.
Festinger, L. and Carlsmith, J. 1959. Cognitive Consequences of
Forced Compliance. Journal of Abnormal and Social Psychology, 58,
203-210.
Tim McNamara
KB <kbe...@earthlink.net> wrote:
> Seriously though, is it inconceivable that one would notice a difference at
> speed with a set of tri-spokes? I mean, they are proven to be more
> aerodynamic than a regular wheel.
Here's the problem with this: notice it through what sensory mode?
Would you feel faster air speed? Would you feel less pedalling effort?
When you are riding at maximum you are riding at maximum- it's going to
feel the same on any reasonable wheelset. Subjective sensation is an
unreliable mode for this sort of thing.
Where the difference will be noticed will be on the stopwatch, and
there is reason to expect that a wheel that is significantly more
aerodynamic would produce a measurable difference.
TC
Have you actually ridden a set of Dura Ace wheelset for for than 50
miles?
TC
Bernie Yee
Are you saying then, that there's little performance difference btw my
trusty Fir isidis tubulars and the Rolf Vector Pros?
-Bernie
"Jobst Brandt" <jbr...@hpl.hp.com> wrote in message
news:8kvr9o$lkf$1...@hplms2.hpl.hp.com...
> TC writes anonymously:
>
> > Does anyone else actually make an attempt to ride away from others who
> > are traveling at 26 MPH?
>
> Is this a rhetorical question or do you ride alone? Watching someone
> pull away, on a casual ride as well as a race, gives the slower rider
> the impression of acceleration, when in fact it is not, assuming the
> tempo is more than insignificant.
>
> > If there isn't any significant difference in all the different
> > wheelsets, why not everyone ride the same old 36 spoke tubulars?
>
Mark McMaster
>
> Mark McMaster wrote:
>
> >To see that Shimano's wheels, with their spokes attached to
> >the sides of the rim, have pathetic lateral stiffness, see:
> >http://www.damonrinard.com/wheel/index.htm
> >
>
> I don't particularly care for the tone of this discussion. Which
> is why I will pose the following questions to Mr. McMaster,
> who deems it OK to take the piss out of someone because
> they stepped on his toes:
>
> Who cares if Shimano wheels have pathetic lateral stiffness,
> since all wheels only experience a "few" pounds of lateral
> loading during their usage?
>
> How does lateral stiffness effect cycling performance?
The reason I brought up the issue of the lateral stiffness
of Shimano wheels was to further show that their spoke
lacing design is a gimmick. On Shimano's web page
(http://www.shimano.com/cycling/wheels/default.htmI) they
make the following claim:
"Lateral Crossover Spoke Pattern: The unique 16-spoke
"lateral crossover" spoke pattern is achieved by anchoring
the threaded end of the spoke through the hub flange
opposite to the side where the spoke head attaches through
the rim sidewall. Wheel dish is greatly reduced, spoke
tension is more uniform, and the wheel's lateral rigidity is
significantly increased so it stays in true longer."
An independent test (which can be found at the web page
referenced in my previous post) showed that the Shimano
wheels have less, not more, lateral rigidity than other 16
spoke wheels (let alone comparing them to "standard" 32
spoke wheels, which are even more rigid). These wheels do
not live up to what they actually claim to do, let alone
what they may merely imply (and some people would like to
believe) they do.
> Since you advocate increased/high lateral stiffness,
> please share your objective, fact based answers to the
> questions I have posed above. Please don't speculate or
> make any highly subjective remarks. I will only accept
> factual, experimentally acquired data in response.
I did not advocate increased/high lateral stiffness, nor in
this discussion make any statements regarding lateral
loading of wheels during use or its effects on cycling
performance. These are your inferences only. I merely
pointed out that Shimano's wheels did not even come close to
meeting their claim regarding lateral stiffness. Why do you
believe that I advocated increased/high lateral stiffness?
(To take a page from your book, please don't speculate or
make any highly subjective remarks. I will only accept
factual, experimentally acquired data in response.)
> If you expect that everyone should be held to these
> standards you proclaim, then so shall you...
... and likewise you, I hope.
Do you believe that a rider can sense from the saddle
whether 15 grams of nipples are at the rim or the hubs?
Mark McMaster
McMa...@Setra.com
Bernie Yee
But your comment is interesting -- Heliums are aerodynamically identical to
32 spoke box rim wheelsets. Hope I'm not digging up old info, but what
tests?
"Jon Isaacs" <joni...@aol.com> wrote in message
news:20000717092635...@ng-bk1.aol.com...
Jobst Brandt
>> Those who claim to feel these differences are imagining effects from
>> having bought more esoteric and expensive wheels that must live up to
>> expectations.
> So, what bike and wheel features offer noticable and/or measureable
> differences in speed, stability, and comfort?
That's the problem, there is no difference in speed for any but riders
in top competition. There definitely is no advantage in stability and
comfort and I assume you mean how the bicycle handles when you say
stability. Wheels have no radial compliance to speak of. The tires
do that.
The main difference is durability and cost. Most of these esoteric
wheels cannot be repaired at home even by a skilled wheel builder
because it takes special equipment. Most 16-spoke wheels cannot be
tightened without a compression box that allows unloading spokes to a
point were they can be adjusted without twisting. Besides that, one
broken spoke makes the wheel unusable, something that doesn't bode
well with anyone who likes to ride a bit on weekends. As long as you
have a follow car with spare wheels, you can get a way with this stuff
but it's not the reality of bicycling to assume that these expensive
toys will extend your bicycling range.
Jobst Brandt <jbr...@hpl.hp.com>
Bob Mitke
>That's the problem, there is no difference in speed for any but riders
>in top competition. There definitely is no advantage in stability and
>comfort and I assume you mean how the bicycle handles when you say
>stability. Wheels have no radial compliance to speak of. The tires
>do that.
Please define how you would quantify and measure "comfort"...
I would agree with your comfort analysis for 0 Hz (quite limited and short
sighted in a scientific sense - something a "C" level college sophomore might
do in a lab - I would bet a PhD would do a much closer investigation of
all the variables and possible excitation frequencies before making such
a bold claim). I am going to wait for someone to post the radial
frequency response of bicycle wheel systems up to the 800 Hz range
before I make any hasty decisions on this topic...
If you want to go ahead and jump to a conclusion, hey, that's
your call....
-Bob "FFT" Mitke
Bob Mitke
>>TC wrote:
>> If there isn't any significant difference in all the different
>> wheelsets, why not everyone ride the same old 36 spoke tubulars?
>
>You're using Bob Mitke'isms here. You claim to feel the difference
>and on the basis of acceleration, and that is what is not happening.
>not that light weight is unimportant or that fewer spokes have less
>drag.
Geez, I'm honored... I've got the master quoting my name...
I wonder if someone can perceive the measurably lower rolling
resistance of Avocet FasGrips compared to the green Michelin
Axial Pro's in a blind test?
-Bob Mitke
Bob Mitke
>The reason I brought up the issue of the lateral stiffness
>of Shimano wheels was to further show that their spoke
>lacing design is a gimmick.
Well, then why didn't you say so originally? Us dumb
consumers might incorrectly assume something you
didn't really want us to assume in the first place...
From the stance you were taking, I incorrectly assumed
you were advocating high lateral stiffness for the
masses...
Simple as that...
>Do you believe that a rider can sense from the saddle
>whether 15 grams of nipples are at the rim or the hubs?
Having never actually conducted a blind test that
addressed the topic of 15 grams of nipple mass at the
hub or rim, (and subject to the high standards you
proclaim everyone must meet) I can't state an
answer to your question...
I would only be speculating...
-Bob Mitke
Bob Mitke
>Bob, Bob, Bob. Didn't you ever read that book on logic I recommended?
I must have misplaced that reference. What was it again (seriously), I
seem to have some spare time on my hands lately and could use a
bit new reading material...
>Your last statement is putting words in Mark's mouth and is, if I
>recall the term correctly, an example of sophistry.
I am flattered, Tim... To know that you think I am clever...
>This sort of thing is suggestive of a weak position- an argument
>lacking in radial and lateral stability as it were. True it up,
>improve the bracing angle and try again. ;-)
I'll try better next time Tim... Though, I was thinking of increasing
the spoke count or the rim Iyy the next time around...
-Bob Mitke
Bob Mitke
>Lateral loading might be minimal under most conditions, but what if you
>clip a pedal and your rear wheel hops sideways?
You had better hope that the designer of your wheels knew what the
*&^# they were doing...
>How many pounds of
>lateral force do you suppose the rear wheel of our tandem encountered
>when we did this in a points race criterium one time?
A significant magnitude...
>> How does lateral stiffness effect cycling performance?
>
>See above. Also, a rear wheel with inadequate lateral stiffness may rub
>on the brake blocks during high power efforts, esp. climbing.
Hmmm... Could it be that Andrew has had an experience of a lateral
load greater than a few pounds during a normal riding experience?
I think you will have a hard time attributing brake block rub to
torque loads, but lateral loads is a definite possibility...
Andrew: push laterally on one of these wheels (at the ground contact point
when the wheel is fixtured in your bike normally)
that you have quoted as rubbing brake blocks and estimate
the magnitude of the force required to get the rim to actually touch the
brakes. Even if the wheel has a paltry lateral stiffness value, the
force required is more than a few pounds...
Let me (and everyone else reading) know the results of your test...
>Note: neither of the above comments should be construed as implying that
>the Shimano wheels are not stiff enough laterally. I'm merely pointing
>out examples that you overlooked in your haste to stir up trouble.
>
I didn't really overlook the lateral stiffness/performance issue, but thanks
for lending your PhD to some of my own personal observations...
Thanks for the disclosure and the assist in my plight...
You have touched on the crux of the lateral stiffness dilemna:
what is stiff enough? As you have also pointed out: it depends on the
end user/usage...
Tricky little subject, huh?
-Bob Mitke
Bob Mitke
Peter Chisholm wrote:
>McMaster wrote a really great piece as to why the weight at the rim meant
>nada-(M(eff)=M+I/R^2)=M+(M*R^2)/R^2)=M=M-2*M) or some such thing.
>Don't think it's stepping on any toes but actually explaining how weight at
>the
>rim means less than a Powerbar in your pocket.
He then went on to confuse the topic with some blathering about
lateral stiffness...
Que bueno que puede hablar Espanol...
Espero que conocer a ti en Las Vegas para el Interbike...
Hasta Pronto,
-Bob "El Pendejo" Mitke
Jon Isaacs
> Have you actually ridden a set of Dura Ace wheelset for for than 50
>miles?
Please explain how riding a set of wheels allows you to determine that your
perceived differences in performances are the result of moving 15 grams from
near the edge of the wheel towards the center.
Also please explain how you measure and account for the variation in the mass
of the your person and of the bicycle. Did you weigh the various wheel sets
you have ridden in order to determine which is lighter?
Jon Isaacs
Jon Isaacs
>addressed the topic of 15 grams of nipple mass at the
>hub or rim, (and subject to the high standards you
>proclaim everyone must meet) I can't state an
>answer to your question...
>
>I would only be speculating...
I would make the speculation that even with extreme accurate instruments
measuring the riders power input as a function of time, the velocity profile of
a ride, the instaneous wind velocity as a vector, the humidity, temperature and
density of the air, the change in the riders mass as he/she exhales CO2 and
H20, it would be difficult in a blind test to determine from the velocity/time
data, the placement of 15 grams of mass on the wheel.
If someone asked me if I could do it, i would say it is unlikely that I could.
There are just too many variables and this effect is just too small. This
mass of concern is something like 1 part in 4000 of the system mass, and since
aerodynamics is by far the largest factor in both the energy and/or power
balances and small changes in the wind cause effects that are at least second
order (energy) in drag, it is pretty clear that such a measurement would be
impossible.
jon isaacs
Jon Isaacs
>32 spoke box rim wheelsets. Hope I'm not digging up old info, but what
>tests?
>
Check out www.damonrinard.com and follow the aerodynamic links.
jon isaacs
Jon Isaacs
>resistance of Avocet FasGrips compared to the green Michelin
>Axial Pro's in a blind test?
>
Sounds like a good idea. Since it was yours, why not try it and make a
positive contribution to this group. Should be able to handle this for $100.
My guess is that in a blind test you could not tell, but kindly let us know the
results.
jon isaacs
Andrew Coggan
> I wrote:
> >Also, a rear wheel with inadequate lateral stiffness may rub
> >on the brake blocks during high power efforts, esp. climbing.
>
> Hmmm... Could it be that Andrew has had an experience of a lateral
> load greater than a few pounds during a normal riding experience?
With a pedal plant/sideways hop, yes. But other than that the only time I've
*personally* experienced brake block rub is during standing climbing on our
tandem, when the front wheel has a tendency to hit the brake pads if they're
very close to the rim. I don't know what's flexing, but the nearly 1" diameter
fork blades have got to be a lot stiffer than the wheel, which although it has
48 spokes, has a very shallow rim.
> I think you will have a hard time attributing brake block rub to
> torque loads, but lateral loads is a definite possibility...
Perhaps I should have specified out-of-the-saddle, high power efforts.
> Andrew: push laterally on one of these wheels (at the ground contact point
> when the wheel is fixtured in your bike normally)
> that you have quoted as rubbing brake blocks and estimate
> the magnitude of the force required to get the rim to actually touch the
> brakes. Even if the wheel has a paltry lateral stiffness value, the
> force required is more than a few pounds...
How can you say this when you don't know how true my wheels are, and how close
to the rims I like to keep the brake pads? :-)
> Let me (and everyone else reading) know the results of your test...
Here's another test: take a marker and color the entire brake track of your rear
wheel. Then set the brake pads close to the rim, and go do some hard efforts
both in and out of the saddle (and of course don't touch the rear brake). I
haven't tried this, but people I know who have report that they find clear
evidence that the brake pads hit the rim, so obviously something must be
flexing.
> You have touched on the crux of the lateral stiffness dilemna:
> what is stiff enough? As you have also pointed out: it depends on the
> end user/usage...
>
> Tricky little subject, huh?
Well, trickier than you at first thought.
Andrew Coggan
Qui si parla Campagnolo
differences in speed, stability, and comfort? >>
Performance features that work on any bike-
Fit-does the bike fit you?
Fitness-are you in good shape?
Fat-less on yer butt the better
Finesse-know how to ride yer bike efficiently?
Peter Chisholm
"Vecchio's" Bicicletteria
1833 Pearl ST.
Boulder, CO
(303)440-3535
http://www.vecchios.com
Peter Headland
> from others who are traveling at 26 MPH?
Yeah, all the time, it's easy. What's that you say? "Forwards?" Oh sorry, I
thought you meant riding off the back of the bunch....
--
Peter Headland, Matrix Link, UK
Pe...@matrixlink.com
http://www.matrixlink.com/
Bob Mitke
> Bob Mitke wrote:
>>I wonder if someone can perceive the measurably lower rolling
>>resistance of Avocet FasGrips compared to the green Michelin
>>Axial Pro's in a blind test?
>>
>
>Sounds like a good idea. Since it was yours, why not try it and make a
>positive contribution to this group. Should be able to handle this for $100.
Your answer to my question was my contribution, since it points
out the hypocrisy of some people who post on this group...
None of this stuff (inertia, tire rolling resistance, etc..) really matters in
terms of increased performance to the average
recreational cyclist. To take the moral high ground on one topic (wheels),
then turn around and claim superiority on another topic which uses
similar marketing claims (low rolling resistance on tires) is silly...
Someone needs to point that out. I assumed that responsibility...
If you want me to run the test, I would be glad to do it. Just mail me
the tires and we can discuss the details later...
$100 is $100...
>My guess is that in a blind test you could not tell, but kindly let us know
>the
>results.
Thank you for lending respectability to my initial assumptions...
In my _opinion_, I would also think you could not tell the difference, just
like you could not tell the difference in two wheels that differed in 15 grams
irrespective of whether that extra 15 grams was at the rim or at the hub...
In absence of a test, all we can do is speculate. TC speculates with the
seat of his pants, Mark M. speculates with some nifty formulas. They are
both speculation, one's just a little bit subjective, that is all...
Mark's plight with TC and inertia is similar to my plight with you all and
lateral stiffness/lateral loads. The difference being that I don't tell you
to shut up. I just keep providing examples and asking questions,
because, for whatever reason, I know that sooner or later you all will
come around to realizing that when you are out of the saddle
climbing a hill, going around a corner and hit a bump, etc.. lateral loads
are larger than a few pounds...
My questioning of Mark M was not an affront on what he was
saying, but rather the approach he was taking. He doesn't hold himself
to those same standards he requires. This needs to be pointed out...
Like I said, I would be happy to do the test you requested, but I won't
do it for a net loss (I would donate my time, though)...
We could probably find much more exciting topics to test, though...
-Bob Mitke
Bob Mitke
>But other than that the only time I've
>*personally* experienced brake block rub is during standing climbing on our
>tandem, when the front wheel has a tendency to hit the brake pads if they're
>very close to the rim. I don't know what's flexing, but the nearly 1"
>diameter
>fork blades have got to be a lot stiffer than the wheel, which although it
>has
>48 spokes, has a very shallow rim
Do you think the lateral load required to cause front wheel deflections
that large are around 3 pounds?
>Well, trickier than you at first thought.
Perhaps you are unfamiliar with my stance on lateral stiffness/lateral
loads on bicycle wheels...
Thanks for helping me in my plight with your personal experience and
suggested tests...
-Bob Mitke
Jon Isaacs
>loads on bicycle wheels...
Perhaps rather than just referring to your stance you might just state what
your stance might happen to be. Probably take fewer words and lead to less
confusion.
Just come right out and say it.
My personal stance is that when I am mountain biking I want a wheel that is
laterally stiff. One reason I like a stiff wheel is because there are times
when the wheel is sliding sideways, particularily the front wheel under
braking, sliding down a hill, nearly out of control, banging off rocks and
things.
Also lateral stiffness is important when the riders weight is not centered over
the wheels, such sorts of loading conditions can occur during the benign
"dismounts" that often occur while off roading. When the bike lands a
significant distance from the person previously riding the bike, significant
lateral loads are possible.
Side loads from impacting rocks etc also make a laterally stiff wheel
desireable.
That is my personal stance.
jon isaacs
Eric Salathe
> So, what bike and wheel features offer noticable and/or measureable
> differences in speed, stability, and comfort?
There's this guy who comes on my club rides on a carbon bike w/ aero
wheels. Everytime we get on a flat or slight downhill, there is nothing
I can do to keep up on my traditional frame and 32-spoke MA2 wheel.
Oh, but I come from work and always have a big pannier on the back. And,
by the way, he does have aero bars.
To make up for it, I get him on the climbs.
So, I'd say that, in a fast group ride where small differences are
noticable, a 2 sq-ft box is slightly noticable aerodynamically, but a
couple pounds make little or no difference climbing.
Eric Salathe
TC
of my bike rather than trying to convince people who has not experienced
certain wheelset for themselves.
TC
TC
of my bike rather than trying to convince people who has not experienced
certain wheelset for themselves.
dispute in theory how there isn't any difference, I guess there isn't
any point to do things differently or to improve yourself.
Peter Headland
> lateral stiffness/lateral loads.
Actually, I agree that the lateral loads on wheels when doing stuff like
climbing out of the saddle in a less-than-perfect style are enough to
deflect the rim a couple of millimetres and cause brake rub. I am damn'
certain that it isn't frame deflection.
I feel that simple observation shows that wheels are plenty strong enough
laterally without anyone having to pay special attention to making them so
(otherwise they'd keep collapsing). And I think that their lateral strength
is more than enough precisely because they have to be adequately stiff
laterally that deflections due to "normal" riding are small enough to be
tolerable and when that is true the wheel is automatically also plenty
strong enough laterally. Strength and stiffness are not the same thing, but
they certainly are closely correlated here.
--
Peter "It ain't what you say, it's the way that you say it" Headland, Matrix
b...@my-deja.com
TC <cat...@mail.idt.net> wrote:
> Putting all the tech stuff aside, my time is better spent on the
saddle of my bike rather than trying to convince people who has not
experienced certain wheelset for themselves.>
fancy $700+++ wheelsets, is going to help you graduate from a cat. 4 to
a higher level.
> If you are never able to afford or willing to try new things, only
> dispute in theory how there isn't any difference, I guess there isn't
> any point to do things differently or to improve yourself.>
that "trying" new things doesn't mean you are going make yourself any
faster. Do you really think that 15g less or even 100g less of
"rotating weight" is going to help you improve beyond the cat. 4 range
you're currently in? Like I stated elsewhere, I could give you a set
of ADA wheels (1000g wheelset) and I seriously doubt you could keep up
with most cat. 3 or higher, let alone the "pros". Training, not some
fancy wheelset is going to help you improve. Moreover, the $700
Shimano wheelset you're so fond of is not going to make you any faster
and will be less durable than a good set of custom build wheels costing
$350-400 or less. So, just get on your bike and start training.
Brewster
Sent via Deja.com http://www.deja.com/
Before you buy.
Bob Mitke
>> I would make the speculation that even with extreme accurate instruments
>> measuring the riders power input as a function of time, the velocity
>profile of
>> a ride, the instaneous wind velocity as a vector, the humidity, temperature
>and
>> density of the air, the change in the riders mass as he/she exhales CO2 and
>> H20, it would be difficult in a blind test to determine from the
>velocity/time
>> data, the placement of 15 grams of mass on the wheel.
>>
>> If someone asked me if I could do it, i would say it is unlikely that I
>could.
>> There are just too many variables and this effect is just too small. This
>> mass of concern is something like 1 part in 4000 of the system mass, and
>since
>> aerodynamics is by far the largest factor in both the energy and/or power
>> balances and small changes in the wind cause effects that are at least
>second
>> order (energy) in drag, it is pretty clear that such a measurement would be
>> impossible.
But, blind tests don't require all that instrumentation, thats the beauty.
Just ride one set of wheels, stop, switch wheels, ride the other set,
say which one is faster...
If lots of people choose the right one compared to the wrong one, people
can perceive the difference...
It is really easy to measure wheel inertia. If wheel inertia is lower, then it
is equally easy to make a claim that the wheel accelerates faster. Is any
of this significant, well, I think we all know the answer to that question...
I am not really following your arguments...
-Bob Mitke
Bob Mitke
>Perhaps rather than just referring to your stance you might just state what
>your stance might happen to be. Probably take fewer words and lead to less
>confusion.
>
>Just come right out and say it.
The reason I took the approach that I did was to solicit an unbiased
answer from someone who didn't have a chip on their shoulder and
would never agree with me, or my observations (read Jobst Brandt,
Mark Hickey, Mark McMaster).
I got the answer I was looking for from Mr. Coggan, a respected
contributor to this forum...
I have already stated my stance before, and the brief version is this:
1) people can perceive differences in lateral stiffness of wheels
2) lateral loads must not be ignored when designing bicycle
wheels for fatigue resistance as well as ultimate strength (i.e,
loads encountered during normal usage are greater than a
few pounds)
3) there is a minimum level of lateral stiffness that wheels must
achieve (but, this level is dependent on the end user and usage,
along with CPSC regulations)
4) high amounts of lateral stiffness are not necessarily better
(similar arguments can be made for bicycle frames)
>Also lateral stiffness is important when the riders weight is not centered
>over
>the wheels, such sorts of loading conditions can occur during the benign
>"dismounts" that often occur while off roading. When the bike lands a
>significant distance from the person previously riding the bike, significant
>lateral loads are possible.
>
>Side loads from impacting rocks etc also make a laterally stiff wheel
>desireable.
As Damon has shown, the range of lateral stiffness values is large,
yet, these wheels seem to perform the desired task just fine.
The key unanswered question is: how stiff is stiff enough? Again,
it depends on the end user and usage. One flavor does not fit
all...
What works for Cadel Evans probably won't work for Jon Isaacs...
What works for Jon Isaacs will probably work for Cadel Evans,
but he won't want to ride it because the design is overkill for his
needs... Any hack can overdesign something, the challenge is
in optimizing the design to meet the specifications...
But, me stating these things doesn't really matter, until there is
a consensus that the topic of lateral stiffness even matters. If
you listen to Jobst, Mark M, or Mark H., you would think that
wheels never deflect laterally more than .5 mm.
So, am I still the only one that believes that wheels only see a
few pounds of lateral loading when climbing out of the saddle,
starting from a stoplight out of the saddle, or going around a
corner and hitting some bumps?
Or, do I have company...
-Bob Mitke
Mark Hickey
>But, blind tests don't require all that instrumentation, thats the beauty.
>Just ride one set of wheels, stop, switch wheels, ride the other set,
>say which one is faster...
Great - another chance for you to contribute something meaningful,
Bob. Tell us how this will work, taking into account the variability
involved in such a test. Give us methodology that will allow a
realistic comparison between the wheels, allowing for wind, terrain,
rider fatigue, road surface, barometric pressure, traffic, etc. I
know it's simple because you say it is. Just help me understand.
>If lots of people choose the right one compared to the wrong one, people
>can perceive the difference...
So bike performance is kind of like democracy... I like that. I guess
Cipo was right - Cannondales ARE the best bikes, eh? Dang, mine must
really suck.
Mark Hickey
Habanero Cycles
http://www.cynetfl.com/habanero/
Home of the $695 ti frame
Bob Mitke
>bikes...@aol.comnojunk (Bob Mitke) wrote:
>
>>But, blind tests don't require all that instrumentation, thats the beauty.
>>Just ride one set of wheels, stop, switch wheels, ride the other set,
>>say which one is faster...
>
>Great - another chance for you to contribute something meaningful,
>Bob. Tell us how this will work, taking into account the variability
>involved in such a test. Give us methodology that will allow a
>realistic comparison between the wheels, allowing for wind, terrain,
>rider fatigue, road surface, barometric pressure, traffic, etc. I
>know it's simple because you say it is. Just help me understand.
Once again, Mark, you miss the point because Bob Mitke wrote
the post...
If you actually did the test properly (concealing only the identity of the
wheels and not controlling the other variables that you mention) with
100 people you would probably find that 55 people choose one wheel,
and 45 people choose the other wheel.
To me, that is convincing evidence that people can _not_
perceive a difference in 15 grams of wheel weight.
Now, if 85 people choose the wheel with 15 grams less as
being faster and 15 people choose the heavier wheel, I would
say that is convincing evidence that people _can_ perceive the
difference and there is something to the wheel inertia thing...
If there is still something that you don't understand about the
test I proposed, ask some more questions, and I am sure we
can get to the bottom of your misunderstanding...
>>If lots of people choose the right one compared to the wrong one, people
>>can perceive the difference...
>
>So bike performance is kind of like democracy... I like that. I guess
>Cipo was right - Cannondales ARE the best bikes, eh? Dang, mine must
>really suck.
If you say your bikes suck, fine. That is your call. I think people can
get a frame for much cheaper than your bikes that perform the same
task just as well as your frames...
Be careful Mark, if you read my other posts in this thread, you will see
you are just proving my point that you will never agree with anything I
ever say, simply because you have a chip on your shoulder...
-Bob Mitke
Bob Mitke
Thanks for the contribution. Your ability to set your ego aside
(since you and I have crossed paths in the past) and say the
things you have said on this topic is admirable...
I agree with your quote above, but, that is my style - I believe that
style is what upsets so many people because deep down they
know what I say has a lot of substance to it, but they just can't
seem to bring themselves to concede _any_ points to the evil
Bob Mitke...
I think my style has evolved over the past six months to a
more temperate one (and that is good if you ask me)...
However, if someone is not consistent with their position, I
will ask questions and pose legitimate, intelligent follow-ups...
-Bob Mitke
Chris Fabri
:
: Your answer to my question was my contribution, since it points
:
: None of this stuff (inertia, tire rolling resistance, etc..) really matters in
: terms of increased performance to the average
: recreational cyclist. To take the moral high ground on one topic (wheels),
: then turn around and claim superiority on another topic which uses
: similar marketing claims (low rolling resistance on tires) is silly...
:
: Someone needs to point that out. I assumed that responsibility...
<snip>
Again, you're missing the point. DId Jon claim he could tell the
difference? No.
:
: In absence of a test, all we can do is speculate. TC speculates with the
: seat of his pants, Mark M. speculates with some nifty formulas. They are
: both speculation, one's just a little bit subjective, that is all...
:
Application of the laws of physics is just speculation?
<snip>
:
: My questioning of Mark M was not an affront on what he was
: saying, but rather the approach he was taking. He doesn't hold himself
: to those same standards he requires. This needs to be pointed out...
:
Bob, I've tried to follow your arguments on this thread, but I've
given up. I don't have a clue what you're trying to get at. You
accuse Mssrs. Brand, McMaster, and Hickey of having a chip on their
shoulders, yet they are the few posters who actually supply useful,
factually correct info *not* based on subjective observations. Yet
you insist that they simply won't accept that you are right. Maybe
it's because they are right, and you are the one who can't accept
criticism, or look objectively and critically at the subject at hand.
chris
--
_________________________ __________________________________________
| Chris Fabri | Northwestern University |
| fab...@northwestern.edu | Telecommunications and Network Services |
| 847-467-2539 | http://www.nsg.northwestern.edu |
|_________________________|__________________________________________|
Jobst Brandt
> Bob, I've tried to follow your arguments on this thread, but I've
> given up. I don't have a clue what you're trying to get at. You
> accuse Mssrs. Brandt, McMaster, and Hickey of having a chip on their
> shoulders, yet they are the few posters who actually supply useful,
> factually correct info *not* based on subjective observations. Yet
> you insist that they simply won't accept that you are right. Maybe
> it's because they are right, and you are the one who can't accept
> criticism, or look objectively and critically at the subject at
> hand.
Chris, from the day he got here, Bob has been purely argumentative
giving contra to practically anything sensible that has been offered.
Not only that, but he goes at it in an ad hominem manner that is
primarily abrasive. I characterize him as a technical troll, although
he doesn't restrict himself entirely to technical matters if none are
offered as targets of opportunity.
Jobst Brandt <jbr...@hpl.hp.com>
Mark Hickey
>Mark Hickey wrote:
>
>>bikes...@aol.comnojunk (Bob Mitke) wrote:
>>
>>>But, blind tests don't require all that instrumentation, thats the beauty.
>>>Just ride one set of wheels, stop, switch wheels, ride the other set,
>>>say which one is faster...
>>
>>Great - another chance for you to contribute something meaningful,
>>Bob. Tell us how this will work, taking into account the variability
>>involved in such a test. Give us methodology that will allow a
>>realistic comparison between the wheels, allowing for wind, terrain,
>>rider fatigue, road surface, barometric pressure, traffic, etc. I
>>know it's simple because you say it is. Just help me understand.
>
>Once again, Mark, you miss the point because Bob Mitke wrote
>the post...
...poorly. Then you added....
>If you actually did the test properly (concealing only the identity of the
>wheels and not controlling the other variables that you mention)
So now all you have to do is tell us how you plan to conceal the
identity of the wheels. Seems like a pretty difficult thing, since
anything you'll do to mask the construction (i.e. location of the
nipples) will obviously have a much bigger impact than the difference
between the (unmasked) wheels.
> with
>100 people you would probably find that 55 people choose one wheel,
>and 45 people choose the other wheel.
>
>To me, that is convincing evidence that people can _not_
>perceive a difference in 15 grams of wheel weight.
>
>Now, if 85 people choose the wheel with 15 grams less as
>being faster and 15 people choose the heavier wheel, I would
>say that is convincing evidence that people _can_ perceive the
>difference and there is something to the wheel inertia thing...
Which would take the whole thread back to the statistics nightmare of
previous threads. I doubt (as you do apparently) that it would be
possible to draw a definite conclusion based on this test.
>If there is still something that you don't understand about the
>test I proposed, ask some more questions, and I am sure we
>can get to the bottom of your misunderstanding...
I think I summed up the questions pretty well. Your turn.
>>>If lots of people choose the right one compared to the wrong one, people
>>>can perceive the difference...
>>
>>So bike performance is kind of like democracy... I like that. I guess
>>Cipo was right - Cannondales ARE the best bikes, eh? Dang, mine must
>>really suck.
>
>If you say your bikes suck, fine. That is your call. I think people can
>get a frame for much cheaper than your bikes that perform the same
>task just as well as your frames...
I'd suggest Huffy, Bob. Same form factor, and a lot less money.
>Be careful Mark, if you read my other posts in this thread, you will see
>you are just proving my point that you will never agree with anything I
>ever say, simply because you have a chip on your shoulder...
Heh heh heh... you're taking yourself WAY too seriously again, Bob.
I've agreed with you several times. Every time you were right,
actually. ;-)
Mark McMaster
> The reason I took the approach that I did was to solicit an unbiased
> answer from someone who didn't have a chip on their shoulder and
> would never agree with me, or my observations (read Jobst Brandt,
> Mark Hickey, Mark McMaster).
Well, I for one am proud and happy to be on Bob's "enemies"
list.
In this particular thread I primarily presented facts and
data (such as nipple weights, effective inertias, etc.),
often supplied with references (such as Francois Grignon's
moment of inertia tests), so I'm not sure how my answers can
be be considered biased.
Mark McMaster
MMc...@ix.netcom.com
Phil Holman
rims touching the brake pads when cranking. This was more than .5 mm and an
obvious fault that needed fixing. I used to open up the pads on the back
wheel to allow for this. Other than that the wheels worked fine so the
design criteria should be "stiff enough not touch the brake pads when
cranking out of the seat'.
Phil Holman
Phil Holman
>Didn't they also do some other things to address the lateral stiffness
issue
>besides adopting outboard bearings?
The X beams ...I think they are a joke.
>
>Could you estimate the lateral load (when applied at the road contact
point)
>that was required to cause brake pad rub on your old set of Rev-X's? Was
it
>more than 5 lbs? 15 lbs? 25lbs? 50 lbs? Or was it less than 3 lbs?
Speculation on my part but I think the deflection was due to excessive axle
flex as a result of the bearings being too far from the dropouts.
Pushing the rim adjacent to the brake pad took an estimated 15 lbs to make
contact which wasn't much different from my conventional wheels.
I assumed the weight on the back wheel in combination with the high chain
tension when cranking was causing too much axle flex.
>
>If you don't mind me asking, how much do you weigh?
175 lbs
Phil Holman
>
>-Bob Mitke
Bob Mitke
>Chris Fabri writes:
>
>> Bob, I've tried to follow your arguments on this thread, but I've
>> given up. I don't have a clue what you're trying to get at. You
>> accuse Mssrs. Brandt, McMaster, and Hickey of having a chip on their
>> shoulders, yet they are the few posters who actually supply useful,
>> factually correct info *not* based on subjective observations.
You are unfamiliar with past encounters with the aforementioned. If
you are curious, check out Deja and do a search...
Sometimes oversimplified analysis techniques
can lead to oversights...
As far as following my arguments on this thread allow me to
summarize them:
1) Does wheel inertia significantly effect the performance of
recreational cyclists?
Of course not... I never argued this point. I did take exception
to the attitudes some people took/still take toward those people
that are less "equation oriented"...
2) Can you conduct a blind test on wheel inertia that will
yield meaningful results?
Of course. Ask Andrew Coggan or Tim McNamara about
the statistics...
3) Does tire rolling resistance significantly effect the performance
of recreational cyclists?
Of course not... Jobst would have you believe otherwise, primarily
because he helped design the Avocet FasGrip (which used the
lower rolling resistance pitch in their ad campaign).
4) Is arguing that tire rolling resistance is significant in one thread
and then turning around and arguing that wheel inertia is
insignificant in another thread hypocritical?
Of course...
5) Should everyone have to provide hard data in order to present an
argument?
Of course not. If that were the case, we would lose the majority of
topics to argue about. And, even if you did have hard data, someone
would find something wrong with the method used to obtain it...
Listen, the reason I pose contrary arguments most of the time is
because it helps people learn... If you soundly know all the concepts
involved about the topic, you should be able to answer my questions
fully and completely (ask Phil Holman how nicely this concept works,
or do a search for "Jerk and the wheel system").
If you don't know the material, you will argue
circles. I can also argue circles... Ask Andrew Coggan about how
good he and I are at arguing circles when the material _is_ known
(eventually someone gets tired; I even got tired on that one)...
But, people will learn (those discussing and anyone reading)
as a result of a topic being discussed intelligently
from both sides. If no one argues, then no one learns about the
topic at a deeper level. The key is to argue more or less civilly, which
is difficult sometimes in this "detached" medium...
>Chris, from the day he got here, Bob has been purely argumentative
>giving contra to practically anything sensible that has been offered.
I am glad you included the word "practically"... After all, I never
argued that wheel inertia was significant like you argue that
rolling resistance _is_ significant...
Of course, you think that wheels never experience more than a
few pounds of lateral loading either...
It took six months, but finally, I have a few respected contributors
on my side now that think significant sideloads are generated
when climbing out of the saddle, going around corners and hitting
a bump (all normal usage conditions if you ask me)...
Are they lying about their own experiences Jobst, or do you
require some hard data before you will believe them?
>Not only that, but he goes at it in an ad hominem manner that is
>primarily abrasive. I characterize him as a technical troll
Wow, I am truly honored...
I have my own Jobst classification...
>although
>he doesn't restrict himself entirely to technical matters if none are
>offered as targets of opportunity.
Advice: don't offer any targets of opportunity...
-Bob "Am I Evil? - Metallica" Mitke
Bob Mitke
>So now all you have to do is tell us how you plan to conceal the
>identity of the wheels. Seems like a pretty difficult thing, since
>anything you'll do to mask the construction (i.e. location of the
>nipples) will obviously have a much bigger impact than the difference
>between the (unmasked) wheels.
If I was devising a blind test to determine human sensitivity to wheel
inertia/weight effects, I would be clever about it and not try to mimic
the example of nipples at the hub/rim given. Is what I would do is
build two identical wheels and apply lead tape under the rim strip
in increasing amounts until I achieved high statistical confidence
in my results...
Often times it helps to think outside the box when tackling
challenging problems...
-Bob "Look before you Leap" Mitke
Bob Mitke
>Spinergy relocated their wheel bearings outboard of the spokes due to the
>rims touching the brake pads when cranking. This was more than .5 mm and an
>obvious fault that needed fixing. I used to open up the pads on the back
>wheel to allow for this. Other than that the wheels worked fine so the
>design criteria should be "stiff enough not touch the brake pads when
>cranking out of the seat'.
Didn't they also do some other things to address the lateral stiffness issue
besides adopting outboard bearings?
Could you estimate the lateral load (when applied at the road contact point)
that was required to cause brake pad rub on your old set of Rev-X's? Was it
more than 5 lbs? 15 lbs? 25lbs? 50 lbs? Or was it less than 3 lbs?
If you don't mind me asking, how much do you weigh?
-Bob Mitke
Mark Hickey
But Bob, how you gonna factor in the aerodynamic effects of moving the
nipples, which should outweigh the intertial effects by an order of
magnitude? You're not going to really answer the question (is wheel A
really faster than wheel B) without taking that into account.
>-Bob "Look before you Leap" Mitke
Is that a promise?
Mark Hickey
I have experimentally determined that a well-used pair of Spinergy
wheels can be moved laterally by more than 0.5mm with the application
of a lateral load of less than three pounds.
Of course, the lateral play that Spinergy wheels are famous for is due
to play in the bearings, so it doesn't mean squat. The same is true
for all wheels to some point - that is, a certain amount of lateral
movement is due to play in the bearings (less of an issue with cup and
cone bearings than the "new improved high tech" sealed cartridge
bearings, which have to compromise between lateral play and rolling
friction).
Oops, there I go again, submitting actual information to a BM thread.
Gee I must really have it in for the guy.
Andrew Coggan
> 2) Can you conduct a blind test on wheel inertia that will
> yield meaningful results?
>
> Of course. Ask Andrew Coggan or Tim McNamara about
> the statistics...
Now why exactly are you mentioning my name in this context?
> 3) Does tire rolling resistance significantly effect the performance
> of recreational cyclists?
>
> Of course not... Jobst would have you believe otherwise, primarily
> because he helped design the Avocet FasGrip (which used the
> lower rolling resistance pitch in their ad campaign).
I think the answer to the question may depend on how you define
"recreational" and "significantly". Overcoming rolling resistance is much
less important than moving air molecules out of the way or lifting your mass
against gravity, but differences in rolling resistance within the range of
what has been measured for different tires can still have what I at least
consider a significant impact upon e.g., 40k TT time.
> 4) Is arguing that tire rolling resistance is significant in one thread
> and then turning around and arguing that wheel inertia is
> insignificant in another thread hypocritical?
>
> Of course...
Again, I'd have to say not necessarily (see above). Besides, AFAIK no one in
this thread has said that wheel interia isn't important, all they've said is
that DIFFERENCES in wheel inertia due to moving the nipples from the rim to
the hub are not important.
Andrew Coggan
Peter Headland
> and then turning around and arguing that wheel inertia is
> insignificant in another thread hypocritical?
No. Because you can calculate the difference in rolling resistance as a time
difference over a reasonable distance. Enough of a time difference to be
worthwhile in a time trial, certainly. You dragged in the straw man of
"recreational rider".
I agree with Jobst that grip and rolling resistance are two useful measures
of tyre quality and represent sensible design goals. I agree with you that
looking cool is another sensible design goal, but no measure of a tyre's
actual fitness for purpose.
> It took six months, but finally, I have a few respected contributors
> on my side now that think significant sideloads are generated
Assuming you imagine that I am a "respected contributor" here... Don't
confuse the word "significant" (as in "sufficient that they have an effect")
with "large in magnitude". I agree with "significant", in the sense that
mild brake rub is possible with inadequately-stiff wheels (my back wheel
needs a bit more tension). I don't know how large the magnitude has to be
for that to happen - I guess I should check Damon Rinaard's site.
> when climbing out of the saddle
Agreed.
> going around corners and hitting a bump
I don't agree with that. We debated this a long time ago and it is quite
obvious that you would be thrown to the ground if hitting a bump while
cranked over generated more than a tiny lateral (relative to the wheel
plane) force. Likewise, if you ride into a 45-degree ridge you will fall
off. Likewise initiating a turn does not induce large side loads.
--
Peter Headland, Matrix Link, UK
Pe...@matrixlink.com
http://www.matrixlink.com/
Jon Isaacs
>Just ride one set of wheels, stop, switch wheels, ride the other set,
>say which one is faster...
A blind test which was trying to determine the effect of moving 15 grams of
nipples from the rim to the hub would require such instrumentation.
Establishing that the conditions are identical is necessary to do blind
testing.
My point is simple. Even with the most sophisticated instruments possible, it
would be impossible to measure the difference that moving the nipples from the
edge to center. This is because there are a vast multitude of variables which
are more significant which cannot be controlled to the necessary level. Thus,
doing so by the "seat of the pants" would be even more difficult.
>I am not really following your arguments...
I can see that. MR. TC seemed to think he could detect moving the spoke nipple
from the outside towards the center of the rim.
I am not disputing that one wheel can be faster than another but rather simply
that by riding a given wheel, one can understand why it is faster and make
statements that moving the nipples from the rim to the hub is the reason for
this.
jon isaacs
Jon Isaacs
>being faster and 15 people choose the heavier wheel, I would
>say that is convincing evidence that people _can_ perceive the
>difference and there is something to the wheel inertia thing...
You have not understood this thread. The wheels both weigh the same, it is
just the position of the nipples that is in question. Furthermore, the real
point is not that wheels are faster but rather determining the reason for the
difference.
This is the test we are discussing. Buildt one set of wheels and then add 15
grams to them and then had 100 people test them. Sometimes the mass is added
uniformly at the hub-nipple and sometimes uniformly at the each nipple-rim
intersection. A blind and random scheme would be used with multiple rides.
Do you honestly believe that you could hold the other variables of known
importance to small enough variations the results could be shown to be
dependent on the movement of the rim mass?
I personally do not think that this could be done.
jon isaacs
Bob Mitke
>But Bob, how you gonna factor in the aerodynamic effects of moving the
>nipples, which should outweigh the intertial effects by an order of
>magnitude? You're not going to really answer the question (is wheel A
>really faster than wheel B) without taking that into account.
You can answer both questions if the result of the test is 50 for
wheel A and 50 for wheel B. If the result of the test is 85 for wheel A
(which has 15g of lead tape) and 15 for wheel B, you _might_ have to
do an additional test of your hypothesis (I don't like to waste time
thinking about something that is not likely to happen, its
inefficient)...
Maybe Andrew Coggan, or Doug Milliken could comment on the
measurable aerodynamic difference between nipples at the hub and
nipples at the rim at 25 mph and 0-10 degree yaw. In my opinion,
not even John Cobb would measure a difference...
Furthermore, you could devise the test such that the acceleration
you investigate is from 0 mph to 10 mph in an indoor facility...
Again, you miss the point. You can answer the original question:
"Can people perceive the 15 g inertial difference between two wheels"
with the blind test proposed. If no statistical confidence levels are
found, that means that the majority of people can't perceive the
difference...
I believe that people would not be able to perceive the difference in
the blind test I have proposed. Until someone actually does the
test, all we can do is speculate though (which, oddly, was another
one of my points a while ago)...
If you disagree with my principle, feel free to state otherwise...
Shall we continue?
-Bob Mitke
Jon Isaacs
testing, it has become absurd and isaddressing a conjecture which was foolish
from the beginning.
Attempting to determine if wheels with significant differences are faster is
difficult to do, let alone wheels where the difference are much smaller than
normal variations in several possible other variable.
Jon Isaacs
Chris Fabri
: Jobst Brandt wrote:
: >Chris Fabri writes:
: >
: >> Bob, I've tried to follow your arguments on this thread, but I've
: >> given up. I don't have a clue what you're trying to get at. You
: >> accuse Mssrs. Brandt, McMaster, and Hickey of having a chip on their
: >> shoulders, yet they are the few posters who actually supply useful,
: >> factually correct info *not* based on subjective observations.
:
: You are unfamiliar with past encounters with the aforementioned. If
: you are curious, check out Deja and do a search...
I'm quite familiar with Jobst's posting habits.
:
: Sometimes oversimplified analysis techniques
: can lead to oversights...
I'm not sure what you mean by this. Most of the procedures you've
suggested have been excessively simple.
:
: As far as following my arguments on this thread allow me to
: summarize them:
:
: 1) Does wheel inertia significantly effect the performance of
: recreational cyclists?
:
: Of course not... I never argued this point. I did take exception
: to the attitudes some people took/still take toward those people
: that are less "equation oriented"...
Then why do you claim that people can "feel" the difference between
wheels? You dismiss the use of verifiable rules and instead
insist on the reliability of the human senses.
:
: 2) Can you conduct a blind test on wheel inertia that will
: yield meaningful results?
:
: Of course. Ask Andrew Coggan or Tim McNamara about
: the statistics...
Yes, you can conduct a test. However, without using instrumentation,
you don't have meaningful results. Just because it *feels* faster
doesn't mean it *is* faster. You keep hanging on to this
conjecture.
:
: 3) Does tire rolling resistance significantly effect the performance
: of recreational cyclists?
:
: Of course not... Jobst would have you believe otherwise, primarily
: because he helped design the Avocet FasGrip (which used the
: lower rolling resistance pitch in their ad campaign).
Rolling resistance can have an affect on perfomance, and it is
measurable. As is aerodynamics. Does it affect the recreational
cyclist? What does the recreational cyclist care about performance?
:
: 4) Is arguing that tire rolling resistance is significant in one thread
: and then turning around and arguing that wheel inertia is
: insignificant in another thread hypocritical?
:
: Of course...
Well, if rolling resistance is significant, which there is proof to,
and wheel inertia is insignificant, which you agree to, then it's
not hypocritical. If you can prove that rolling resistance is
insignificant, then do so, and you will have an argument.
:
: 5) Should everyone have to provide hard data in order to present an
: argument?
:
: Of course not. If that were the case, we would lose the majority of
: topics to argue about. And, even if you did have hard data, someone
: would find something wrong with the method used to obtain it...
If you have a claim, you need to back it up with some quantitative
data. Simply claiming "compenent X made me faster because I was
riding 2 miles and hour faster on tuesday than on monday," well,
what proof do you have? You claim there is no lateral forces
on a wheel when a bike is turning. Prove it. How? Present
some data to back up your assertion, and not just "because."
:
: Listen, the reason I pose contrary arguments most of the time is
: because it helps people learn... If you soundly know all the concepts
: involved about the topic, you should be able to answer my questions
: fully and completely (ask Phil Holman how nicely this concept works,
: or do a search for "Jerk and the wheel system").
Posing contrary arguments does indeed help people learn, because
it forces both sides to present data that validates it's position.
So far, all I've seen you do is propose contrary arguments, and
when presented with valid data, you say that quantitative measurements
based the laws of physics are not correct.
:
: If you don't know the material, you will argue
: circles. I can also argue circles... Ask Andrew Coggan about how
: good he and I are at arguing circles when the material _is_ known
: (eventually someone gets tired; I even got tired on that one)...
: But, people will learn (those discussing and anyone reading)
: as a result of a topic being discussed intelligently
: from both sides. If no one argues, then no one learns about the
: topic at a deeper level. The key is to argue more or less civilly, which
: is difficult sometimes in this "detached" medium...
I will certainly agree with you that argument on newsgroups could be
kept to a more civil tone. However, if through repetition
on a correct position with no data to back you up, expect those who
are familiar with the topic to become less civil as your insistance
grows.
:
: >Chris, from the day he got here, Bob has been purely argumentative
: >giving contra to practically anything sensible that has been offered.
:
: I am glad you included the word "practically"... After all, I never
: argued that wheel inertia was significant like you argue that
: rolling resistance _is_ significant...
That's because rolling resistance *is* significant. Wheel inertia
is not going to affect a 40K time. Rolling resistance will. It
is measurable, and tire makers always seek to decrease it. You
can even make a simple experiment to prove it. get a Tune power
tap. Go to the track. Ride around it for 25 miles at a steady
power. Decrease the tire pressure by 20 lbs. Repeat. You
could also try this with different tires at the same pressure. If
you don't believe the statement that rolling resistance isn't significant,
this will give you pretty good proof.
:
: Of course, you think that wheels never experience more than a
: few pounds of lateral loading either...
I don't think he said that.
:
: It took six months, but finally, I have a few respected contributors
: on my side now that think significant sideloads are generated
: when climbing out of the saddle, going around corners and hitting
: a bump (all normal usage conditions if you ask me)...
You are correct on the first assumption, but as others have
pointed out, not on the 2nd two.
:
: Are they lying about their own experiences Jobst, or do you
: require some hard data before you will believe them?
He's not suggesting that they are lying, simply that the observation
is incorrect.
:
: >Not only that, but he goes at it in an ad hominem manner that is
: >primarily abrasive. I characterize him as a technical troll
:
: Wow, I am truly honored...
:
: I have my own Jobst classification...
:
Something to be proud of clearly. While not complimentary, Jobst's
response was certainly civil. You're ironic response is not. Let's
not get civility and criticism confused. chris
Bob Mitke
>Oops, there I go again, submitting actual information to a BM thread.
>Gee I must really have it in for the guy.
Of course, the information you submitted is completely irrelevant to
the topic at hand...
Furthermore, I disagree with your measurement method:
What was the serial and model number for your force measurement
system and what was its quoted uncertainty...
How did you fixture the wheel?
Why didn't you eliminate the bearing variable from the experiment
(lateral stiffness of wheels)?
Hack experiments lead to hack results...
-Bob Mitke
Bob Mitke
>Bob Mitke wrote:
> Of course not... I never argued this point. I did take exception
>: to the attitudes some people took/still take toward those people
>: that are less "equation oriented"...
>
>Then why do you claim that people can "feel" the difference between
>wheels? You dismiss the use of verifiable rules and instead
>insist on the reliability of the human senses.
The only claim I have made regarding feel and wheels is in terms of
lateral stiffness. People can perceive a difference in lateral stiffness...
I have made no such claim that people can perceive a difference in
terms of wheel inertia, in fact I agree with most everyone here that
you can not perceive the difference in 15 grams of weight at the
hub or at the rim...
>Yes, you can conduct a test. However, without using instrumentation,
>you don't have meaningful results.
I disagree. A quick perception test with a small group of
people will lead to valuable, quick, cheaply acquired insight into
a much more complex issue.
If you want your data to stand up in a scientific journal, yes, you
will have to spend hundreds of thousands of dollars to control every
variable and assure absolute accuracy...
To prove the point that people can't perceive the difference of
15 grams at the hub or at the rim in a forum called r.b.t, you
could do it with a statistically insignificant result during a
20 person perception test as I described...
>Rolling resistance can have an affect on perfomance, and it is
>measurable. As is aerodynamics. Does it affect the recreational
>cyclist? What does the recreational cyclist care about performance?
Since I have yet to see a world class cyclist who has reached the
limits of their physical and mental potential to post on this newsgroup,
I would consider us all recreational. There are more significant things
than your tires or your wheels that will effect performance...
>Well, if rolling resistance is significant, which there is proof to,
>and wheel inertia is insignificant, which you agree to, then it's
>not hypocritical.
In the context of a recreational cyclist (as you forgot to
mention as my stipulation) what you say is of no significance... Your
logic is based on incorrect assumptions...
>If you can prove that rolling resistance is
>insignificant, then do so, and you will have an argument.
In the context of a recreational cyclist rolling resistance is
insignificant. Do you really want to argue about this point?
> You claim there is no lateral forces
>on a wheel when a bike is turning.
I make no such claim...
>So far, all I've seen you do is propose contrary arguments, and
>when presented with valid data, you say that quantitative measurements
>based the laws of physics are not correct.
Do some searches, I have posted numerous references to my claims...
I have never said that quantitative measurements based on the laws of
physics are not correct. Conclusions based on poor instrumentation,
incomplete analysis, etc.. have been known to not sit so well with me,
yes...
>That's because rolling resistance *is* significant.
Again, you failed to listen to what I said. Remember the words
"Recreational Cyclist"...
>Wheel inertia
>is not going to affect a 40K time. Rolling resistance will.
Both will effect a 40K time. One will be a larger effect. Both will be
insignificant in relation to other things that a recreational cyclist
(the vast majority of people who purchase expensive bike products)
could do to improve performance...
> You
>can even make a simple experiment to prove it. get a Tune power
>tap. Go to the track. Ride around it for 25 miles at a steady
>power. Decrease the tire pressure by 20 lbs. Repeat. You
>could also try this with different tires at the same pressure. If
>you don't believe the statement that rolling resistance isn't significant,
>this will give you pretty good proof.
Your test is poorly thought out, especially for a 40K effort.
Which would have a greater effect on your 40K time: carefully
selecting the lowest rolling resistance tire, altering tire pressure
by 20 psi, or quitting your job and dedicating all your time to
training...
>: It took six months, but finally, I have a few respected contributors
>: on my side now that think significant sideloads are generated
>: when climbing out of the saddle, going around corners and hitting
>: a bump (all normal usage conditions if you ask me)...
>
>You are correct on the first assumption, but as others have
>pointed out, not on the 2nd two.
I must have been tired, what you call the last two I meant to be one
and should have also included the phrase "out of the saddle" (i.e,
your wheels will experience significant lateral loads if you were to
hit a bump during a cornering maneuver while out of the saddle -
something I do on every ride I go on).
Chalk up another vote for significant lateral loads during normal
riding conditions...
> Wow, I am truly honored...
>:
>: I have my own Jobst classification...
>:
>
>Something to be proud of clearly. While not complimentary, Jobst's
>response was certainly civil. You're ironic response is not. Let's
>not get civility and criticism confused.
Irony, what is that?
I _was_ truly honored...
-Bob Mitke
Bob Mitke
>Bob Mitke wrote:
>> 4) Is arguing that tire rolling resistance is significant in one thread
>> and then turning around and arguing that wheel inertia is
>> insignificant in another thread hypocritical?
>
>difference over a reasonable distance. Enough of a time difference to be
>worthwhile in a time trial, certainly. You dragged in the straw man of
>"recreational rider"
The only context I made my comments in was in the context of
"recreational cyclist"...
>I agree with Jobst that grip and rolling resistance are two useful measures
>of tyre quality and represent sensible design goals.
They also make nice bullets on a marketing brochure which wind up
confusing us simple-minded consumers as to what is really important
in terms of improving performance...
>> It took six months, but finally, I have a few respected contributors
>> on my side now that think significant sideloads are generated
>
>Assuming you imagine that I am a "respected contributor" here...
You seem like a nice enough fellow to me...
>Don't
>confuse the word "significant" (as in "sufficient that they have an effect")
>with "large in magnitude".
I think wheels routinely see lateral loads on the order of 50 lbs and
greater. Is this significant, yes. Large, well, that depends on what
you are comparing it to...
>I agree with "significant", in the sense that
>mild brake rub is possible with inadequately-stiff wheels (my back wheel
>needs a bit more tension). I don't know how large the magnitude has to be
>for that to happen - I guess I should check Damon Rinaard's site
It takes approximately 50 lbs of lateral loading to cause a front Mavic
Cosmic Carbone or a Rolf Vector Pro rear to displace .055 in. at 180
degrees from the load application point (about where your brakes
are)...
That same 50 pound load will cause an early Spinergy to deflect .100
inches between the brakes...
A 32 hole Open pro deflects a scant .030 inches under the same 50
pound side load...
If you don't believe me, measure it yourself...
People didn't mention anything about brake rubbage before
(on properly built wheels) because wheels didn't react to sideloads
in the same way as some wheels do now. The new designs make
these same sideloads our wheels have always experienced
more noticeable now...
>> going around corners and hitting a bump
>
>I don't agree with that. We debated this a long time ago and it is quite
>obvious that you would be thrown to the ground if hitting a bump while
>cranked over generated more than a tiny lateral (relative to the wheel
>plane) force. Likewise, if you ride into a 45-degree ridge you will fall
>off. Likewise initiating a turn does not induce large side loads.
I mentioned in another post that I mis-typed my sentence. I meant
to make the claim about being out of the saddle and hitting
bumps while going around a corner...
I don't understand your 45 degree ridge example, please expand...
-Bob Mitke
Mark Hickey
>Mark Hickey wrote:
>
>>Oops, there I go again, submitting actual information to a BM thread.
>>Gee I must really have it in for the guy.
>
>Of course, the information you submitted is completely irrelevant to
>the topic at hand...
Hmmm. BM tries to use observed lateral movement in a Spinergy wheel
to kick the lateral flex dead horse again, and I point out the fact
that nearly all Spinergy wheels have significant lateral play in the
bearings.
Sounds entirely relevant to me, but I live in a different universe
than BM.
>Furthermore, I disagree with your measurement method:
Which I never mentioned, but I'd expect that.
>What was the serial and model number for your force measurement
>system and what was its quoted uncertainty...
A model 134BZ index articulation unit serial number 1, and a model 563
opposable three joint digit serial number 1. I even doublechecked the
results with functionally identical units on my left hand. I was
quoted as being absolutely certain that the lateral movement was well
over 0.5mm, and that the force to produce such a movement was well
under the magic three pounds. By a lot, if it matters.
>How did you fixture the wheel?
In a titanium structure exhibiting no measureable deflection given the
paltry forces involved. Really nice one, too... it just completed the
PBP ride.
>Why didn't you eliminate the bearing variable from the experiment
>(lateral stiffness of wheels)?
Bob, you need to work on the reading comprehension part of this thing
called "communications" a bit more... You were the one who needs to
do what you suggest, to resurrect your fallen steed. You're the only
one who really seems to care about lateral stiffness of wheels - but
don't seem to want to actually do any tests. Curious.
>Hack experiments lead to hack results...
Sure does - I can't imagine you trying to draw a conclusion about
someone experiencing a bit of brake rub with a Spinergy wheel without
taking the bearing play into account. Pretty sloppy, Bob...
Mark Hickey
>People didn't mention anything about brake rubbage before
>(on properly built wheels) because wheels didn't react to sideloads
>in the same way as some wheels do now. The new designs make
>these same sideloads our wheels have always experienced
>more noticeable now...
Errr, Bob... ever hear of dual pivot brakes? They're very popular now
(i.e. you can't really buy much of anything else) and they have a
fraction of the pad-rim distance of the previous single-pivot
calipers.
Peter Headland
Riding in a straight line on a flat surface you encounter a vertical kerb
(or maybe a piece of wood or the edge of a pothole) at 45 degrees to the
direction of travel. If it is of any significant height (I'm guessing 1/2"
or more for a narrow road tyre?), you will go down. I mentioned this example
because, when all this came up before, you seemed to say this was an example
of how a wheel might encounter a substantial side load. In reality, if one
really has to try to ride over such an obstacle at speed, one both turns to
make the angle of impact less acute and also hops the wheels over.
Bob Mitke
>Bob Mitke wrote:
>>Of course, the information you submitted is completely irrelevant to
>>the topic at hand...
>
>Hmmm. BM tries to use observed lateral movement in a Spinergy wheel
>to kick the lateral flex dead horse again, and I point out the fact
>that nearly all Spinergy wheels have significant lateral play in the
>bearings.
>
>Sounds entirely relevant to me, but I live in a different universe
>than BM.
I made assumptions about Phil Holman's observations (based
on the fact that he is/was a Boeing engineer):
1) that he is entirely competent
2) the brakes he used, when in the opened position as he states
have clearances over .050 in. on either side (quite conservative
assumption on my side - I usually run my dual pivots with at least
.040 in clearance on either side and when I open them up, the
clearance is more like .500 in. on either side) If Phils bearings
have that much play and he still reported what he did, well, then
Phil is incompetent - as you'll see in pt 1 I think Phil is competent)
3) Spinergy wheels are not the only wheels that cause brake pad
rub - which makes your position on Spinergy's sloppy bearings
quite tenuous if you ask me...
>>What was the serial and model number for your force measurement
>>system and what was its quoted uncertainty...
>
>A model 134BZ index articulation unit serial number 1, and a model 563
>opposable three joint digit serial number 1. I even doublechecked the
>results with functionally identical units on my left hand. I was
>quoted as being absolutely certain that the lateral movement was well
>over 0.5mm, and that the force to produce such a movement was well
>under the magic three pounds. By a lot, if it matters.
>
I realize that you are being silly, but your exercise further demonstrates
to me that your reporting/documentation skills are lacking...
>>Why didn't you eliminate the bearing variable from the experiment
>>(lateral stiffness of wheels)?
>
>Bob, you need to work on the reading comprehension part of this thing
>called "communications" a bit more... You were the one who needs to
>do what you suggest, to resurrect your fallen steed. You're the only
>one who really seems to care about lateral stiffness of wheels - but
>don't seem to want to actually do any tests. Curious.
>
I have done the tests, and I have reported the results... Will you
believe me? No. Do the test yourself, as I have suggested, and
then we can talk further (or even check out Damon's web site
that shows significant variation in deflection at 180 degrees from
the load application point for different wheels)...
>>Hack experiments lead to hack results...
>
>Sure does - I can't imagine you trying to draw a conclusion about
>someone experiencing a bit of brake rub with a Spinergy wheel without
>taking the bearing play into account. Pretty sloppy, Bob...
Spinergy wheels are not the only wheels that rub brakes...
Again, the measurements I have made are consistent with peoples
observations. If you look at the steps involved in research,
correlation of your lab results to reality must occur for the
conclusions to have any merit. My results correlate, and I have
people who have voiced support of my position now. You are
taking on more than just fat 'ol Bob...
-Bob Mitke
Bob Mitke
>bikes...@aol.comnojunk (Bob Mitke) wrote:
>
>>People didn't mention anything about brake rubbage before
>>(on properly built wheels) because wheels didn't react to sideloads
>>in the same way as some wheels do now. The new designs make
>>these same sideloads our wheels have always experienced
>>more noticeable now...
>
>Errr, Bob... ever hear of dual pivot brakes? They're very popular now
>(i.e. you can't really buy much of anything else) and they have a
>fraction of the pad-rim distance of the previous single-pivot
>calipers.
The size of your ego is remarkable...
You completely missed the point of my post, including the numbers
you have been dying for from me...
What is the clearance on your dual pivots when you open them up?
Yes, your observation is correct about single and dual pivots,
but I don't generally run my brakes
(single or dual pivots) closer than .040 in. clearance on either side.
The lateral loads applied at the road required to deflect a wheel that
much between the pads are larger than 3 pounds...
Do you wish to argue the aforementioned point about lateral loads
and movement between brake pads (which both I, and Damon Rinard
have measured), or shall I continue to make you look silly...
I don't care what people think about me - you as a businessman
might want to reconsider how the public perceives you...
-Bob Mitke
Bob Mitke
>> I don't understand your 45 degree ridge example, please expand...
>
>Riding in a straight line on a flat surface you encounter a vertical kerb
>(or maybe a piece of wood or the edge of a pothole) at 45 degrees to the
>direction of travel. If it is of any significant height (I'm guessing 1/2"
>or more for a narrow road tyre?), you will go down. I mentioned this example
>because, when all this came up before, you seemed to say this was an example
>of how a wheel might encounter a substantial side load. In reality, if one
>really has to try to ride over such an obstacle at speed, one both turns to
>make the angle of impact less acute and also hops the wheels over.
>
When I come upon an obstacle as you describe, the first thing I do is get
out of the saddle - once this happens - all bets are off...
Exposed oblique railroad tracks are a good example - how often do you ride
across them while still seated?
I also ride mountain bikes in less than ideal conditions - I don't limit my
comments to one style of riding...
You can hop well with front wheels, but if your technique is lacking, the
rear wheel sees the brunt...
-Bob Mitke
George S. Hugh
"Bob Mitke" <bikes...@aol.comnojunk> wrote in message
news:20000721010658...@ng-bd1.aol.com...
> Chris Fabri wrote:
> >Bob Mitke wrote:
>
> > Of course not... I never argued this point. I did take exception
> >: to the attitudes some people took/still take toward those people
> >: that are less "equation oriented"...
> >
> >Then why do you claim that people can "feel" the difference between
> >wheels? You dismiss the use of verifiable rules and instead
> >insist on the reliability of the human senses.
>
> The only claim I have made regarding feel and wheels is in terms of
> lateral stiffness. People can perceive a difference in lateral
stiffness...
>
> I have made no such claim that people can perceive a difference in
> terms of wheel inertia, in fact I agree with most everyone here that
> you can not perceive the difference in 15 grams of weight at the
> hub or at the rim...
>
> >Yes, you can conduct a test. However, without using instrumentation,
> >you don't have meaningful results.
>
> I disagree. A quick perception test with a small group of
> people will lead to valuable, quick, cheaply acquired insight into
> a much more complex issue.
>
> If you want your data to stand up in a scientific journal, yes, you
> will have to spend hundreds of thousands of dollars to control every
> variable and assure absolute accuracy...
>
I agree that quick perception tests can give you a reason to investigate
something, but claims based on such observations cannot be made at a
technical level. This is a technical newsgroup and people want numbers on
topics such as this.