Hub Rolling Resistance - DA vs Ultegra vs 105?
pinnah
the 3 primary lines of hubs in the Shimano line?
My cheap-skate dirt-bag opinion has always been that above the worst
of the hubs, you mostly pay for a) better polish and bling and b)
lower weight but that rolling resistance was largely the same.
If you think there is less rolling resistance in the top end hubs, can
you explain why and how this achieved?
Is it because in the inner surface of the bearing cup is so much
better?
Is it because the cones are so much better? Is there such a thing as
a DuraAce cone that differs in any way from, say, a 105 cone?
Is it because the bearings themselves are so much better? Again, is
there such a thing as a DuraAce ball bearing?
Many thanks,
-Dave
-- Dave
==============================================
"It is impossible, or not easy, to do noble acts
without the proper equipment."
Aristotle, <<Politics>>, 1323a-b, trans Jowett
==============================================
Ron Ruff
alignment... but even a 100% difference would not amount to much. Hub
bearing rolling resistance is ~ 100 times less than tire resistance...
which isn't even very much at high speeds.
jim beam
> Is there any meaningful difference in the rolling resistance between
> the 3 primary lines of hubs in the Shimano line?
not so as you'd notice while riding.
>
> My cheap-skate dirt-bag opinion has always been that above the worst
> of the hubs, you mostly pay for a) better polish and bling and b)
> lower weight but that rolling resistance was largely the same.
>
> If you think there is less rolling resistance in the top end hubs, can
> you explain why and how this achieved?
there's very little measurable in r.r. - the difference is longevity
improved by improved precision and materials.
>
> Is it because in the inner surface of the bearing cup is so much
> better?
adjusted correctly, you won't notice much difference in r.r., just
smoothness.
>
> Is it because the cones are so much better? Is there such a thing as
> a DuraAce cone that differs in any way from, say, a 105 cone?
sure, they're smoother because the precision is better.
>
> Is it because the bearings themselves are so much better? Again, is
> there such a thing as a DuraAce ball bearing?
there's different grade ball and different grade races. as above, if
you're noticing a difference in actual rolling resistance [not
smoothness] the bearings need to be adjusted correctly.
carl...@comcast.net
Dear Dave,
You may be thinking of stuff like this:
2006 FSA Ceramic Hub Bearing Set for Mavic & Zipp Wheelsets $339.99
Item: FSA152
Ceramic bearings reduce drag in your hubs, and they do it in a big,
big way in comparison to the machine-quality cartridge bearings that
come stock in most wheelsets (even high end models) on the market
today. Ceramic bearings are immeasurably-and-thoroughly-devilishly
round, and it's this roundness that gives them their rolling
slickness. The reduction in mechanical drag you get by upgrading to
ceramic bearings is no different than magically shedding pounds off
your bike on a climb. For a given wattage, your speed increases.
Period. According to FSA, the use of their ceramic bearings (including
the specially formulated lubricant they roll in) gives you an added
20m-40m per 1km ridden. And keep in mind that mechanical drag is
utterly unlike aerodynamics -- it becomes more and more critical the
lower your speed is. According to FSA testing, the use of ceramic
bearings decreases friction 22-fold. It's not personal, it's just
physics.
http://www.competitivecyclist.com/za/CCT?PAGE=BUY_PRODUCT_STANDARD&PRODUCT.ID=2858&CATEGORY.ID=830&MODE=
or http://tinyurl.com/rl66t
(Note the weird claim that "mechanical drag becomes more and more
critical the lower your speed is." Mechanical drag rises with load and
speed. It does become a larger part of the total drag as speed drops,
since wind drag is not linear--below about 15 mph, transmission and
rolling resistance are about as big as wind drag. But the notion that
mechanical drag becomes critical at low speeds implies that your
grandmother needs $340 bearings to idle down the block to visit a
friend.)
Below is part of the article "FSA Ceramic Revolution" mentioned in the
ad, from this site:
http://www.fullspeedahead.com/fly.aspx?layout=news&cid=199
(Page down in the inset to get to the "Testing Data" reproduced
below.)
I hope to see entertaining comments about the claims.
Cheers,
Carl Fogel
TESTING DATA
Tests by the Danish magazine Cykel-Motion (Mar 2005) and subsequently
supported by calculation, show how using ceramic bearings can reduce
rolling resistance by 50%, saving 22m in just 55 seconds at 32kph. In
short, astounding speed improvement of 4%.
Further tests by SKF, and confirmed by the Danish cycle magazine Cykel
Magasinet (Sep 2005), describe dramatic reductions in friction
compared to conventional cycle bearings. For example:
With a pair of race wheels (total of six bearings), friction with
ceramic bearings is reduced 22 fold
While Dura Ace pulleys consume 0.78W @ 500rpm, ceramic pulleys use
less than 0.06W
A Record BB @ 100rpm and 400W consumes 0.6W, the same BB with ceramic
bearings consumes 0.02W
Such improvement is unheard of, even in this day of advanced bicycle
technology. So, it comes as no surprise to learn that top professional
riders are already using these amazing bearings to win major races.
Full Speed Ahead has been testing ceramic bearings with our teams for
the past two years. The results are great, teams and riders are
convinced.
The friction reduction of ceramic bearings aids a wide variety of
riders. Unlike aerodynamic features, which only the fastest riders
enjoy, the advantage of ceramic units is greater at lower speeds. This
is a crucial difference between aerodynamic resistance, which
increases exponentially with speed; and mechanical friction, which
increases in direct proportion to speed. From a technical point of
view, riders sheltered inside the peleton or riding off road have more
to gain with ceramic bearings.
Ceramic bearings last longer, perhaps 5-10 times more. From a strictly
economic perspective, they’re less expensive to run even without
considering the labor savings.
Now it’s time to share this exclusive technology with our customers.
Phil Lee, Squid
> Is there any meaningful difference in the rolling resistance between
> the 3 primary lines of hubs in the Shimano line?
IMO, no. My NOS 10-year-old 105 hub bearings were adjusted properly, and
when done, they spun just as smoothly as a cartridge bearing.
If you have the chance, break open a DA hub and a 105 hub and look at the
races/cones. They are probably identical. Now if one's mirror-polished and
the other is not...
--
Phil Lee, Squid
pinnah
><pinna...@THIS.comcast.net> wrote:
>>Is it because the bearings themselves are so much better? Again, is
>>there such a thing as a DuraAce ball bearing?
carl...@comcast.net wrote:
>You may be thinking of stuff like this:
>
>2006 FSA Ceramic Hub Bearing Set for Mavic & Zipp Wheelsets $339.99
>Item: FSA152
That's very interesting (and expensive).
But the FSA bearings are cartridge style and only available for Campy
type hubs, correct?
Can loose ceramic balls be used with traditional cup/cone hubs?
Are they available?
carl...@comcast.net
Dear Dave,
Interesting, expensive, and rather questionable.
Note the claim for a 4% speed increase:
http://www.fullspeedahead.com/fly.aspx?layout=news&cid=199
This calculator . . .
http://www.kreuzotter.de/english/espeed.htm
predicts with defaults, hands-on-drops, and the 400 watts mentioned in
that FSA bearing link . . .
27.7 mph.
A 4% speed increase would mean 28.8 mph, which the calculator predicts
requires . . .
Er, 446 watts, suggesting that the bearing drag eliminated would be 46
watts. I think that most people would be hard pressed to find 46 watts
of bearing resistance in their hubs, pulleys, pedals, and bottom
bracket at 28 mph. That's about 7 watts per bearing.
Cheers,
Carl Fogel
b...@mambo.ucolick.org
> You may be thinking of stuff like this:
> ... According to FSA, the use of their ceramic bearings (including
> the specially formulated lubricant they roll in) gives you an added
> 20m-40m per 1km ridden. And keep in mind that mechanical drag is
> utterly unlike aerodynamics -- it becomes more and more critical the
> lower your speed is. According to FSA testing, the use of ceramic
> bearings decreases friction 22-fold. It's not personal, it's just
> physics. ...
>
> I hope to see entertaining comments about the claims.
Geez, Carl, just post the entire advertising brochure,
why don't you.
The typical power dissipated in front+rear wheel bearings
for a typical rider, traveling at 10 m/s (22 mph) should be
about 0.35 watts, as analyzed here:
<http://groups.google.com/group/rec.bicycles.tech/msg/9306a25dadee264e>
For comparison the total power at 10m/s is of order 210 watts,
of which about 180 W is due to aero drag (depending on the
rider's area, of course). So about 0.17% of power is going
into wheel bearings. Riding on magical frictionless bearings
would save 0.17% of power and increase speed by about 0.06%,
or 0.6 meter per km, not the 20-40 m FSA claims. Of course
ceramic bearings are not actually magical nor frictionless, so
the savings should be less.
> TESTING DATA
>
> Tests by the Danish magazine Cykel-Motion (Mar 2005) and subsequently
> supported by calculation, show how using ceramic bearings can reduce
> rolling resistance by 50%, saving 22m in just 55 seconds at 32kph. In
> short, astounding speed improvement of 4%.
>
> While Dura Ace pulleys consume 0.78W @ 500rpm, ceramic pulleys use
> less than 0.06W
These are referring to derailleur jockey pulley bearings,
and this is very likely horseshit, because the angular
velocity of a jockey pulley is high but the force loading
is very small.
> A Record BB @ 100rpm and 400W consumes 0.6W, the same BB with ceramic
> bearings consumes 0.02W
I require a reputable engineering reference for the coefficient
of friction of ceramic bearings (in typical conditions, not
perfect oilbath or something) before believing this.
IIRC, the Zipp promo material that Lennard Zinn quoted
(what I was responding to in the post linked above) said
that ceramic bearing had about 3-4% less friction than
steel bearings, that is their friction was 0.96-0.97 of
steel bearings.
Ben
carl...@comcast.net
<b...@mambo.ucolick.org> wrote:
>carl...@comcast.net wrote:
>
>> You may be thinking of stuff like this:
>> ... According to FSA, the use of their ceramic bearings (including
>> the specially formulated lubricant they roll in) gives you an added
>> 20m-40m per 1km ridden. And keep in mind that mechanical drag is
>> utterly unlike aerodynamics -- it becomes more and more critical the
>> lower your speed is. According to FSA testing, the use of ceramic
>> bearings decreases friction 22-fold. It's not personal, it's just
>> physics. ...
>>
>> I hope to see entertaining comments about the claims.
>
>Geez, Carl, just post the entire advertising brochure,
>why don't you.
[reluctantly snip entertaining and appreciated comments]
Dear Ben,
Surely you don't consider that an advertising brochure disguised as
test results?
You know, the kind of stuff that could make people wonder if they
could increase their speed 4% with $340 bearings?
Remember, "it becomes more and more critical the lower your speed is!"
:)
Thanks for the technical comments, even though I snipped them. I
thought that someone might have a few minor objections to that
twaddle.
Cheers,
Carl Fogel
Dave Mayer
"pinnah" <pinna...@THIS.comcast.net> wrote in message
news:vgtfb2dabo0eg2hgb...@4ax.com...
> Is there any meaningful difference in the rolling resistance between
> the 3 primary lines of hubs in the Shimano line?
>
> My cheap-skate dirt-bag opinion has always been that above the worst
> of the hubs, you mostly pay for a) better polish and bling and b)
> lower weight but that rolling resistance was largely the same.
I have taken apart and put back together dozens of types of hubs. Unsealed
old-school cup and cone bearing hubs (as made by Shimano and Campagnolo)
have slightly lower rolling resistance than their sealed modern equivalents
(such as the excellent current generation of LX and XT hubs). Cartridge
bearing hubs have about the same rolling resistance as sealed hubs.
Properly set up (and that is the key here), there is no real difference in
rolling resistance between road hubs such as Dura-Ace and 105. You cannot
tell the difference spinning the hub by hand. Dura-Ace and XTR feature
forged bearing cups and cones and stainless bearings - which provides a
greater longevity when dirt and water gets in. Nevertheless, properly set
up and maintained, a 105 or LX hub should pretty much last the life of the
rider. Typically the cheaper hubs are set up too tight, and with too little
grease. This causes roughness, and premature wear.
Finally, the small differences we are talking about here - between different
hubs, or even more of a stretch, different types of ball bearings are so
minor and inconsequential, that they are not even worth thinking about. Go
out and train an extra second per month. That is the magnitude of possible
improvement we are talking about here.
serv...@df.unipi.it
The quality, and the good shape, of a bearing is only told by the noise
it makes while rolling, for which so little power is needed.
Sergio
Pisa
* * Chas
<carl...@comcast.net> wrote in message
news:sn6gb2trrc38cr0r4...@4ax.com...<snip>
BULLPUCKY!
Cyclists tend to be the most gullible group of consumers in the sports
market place - followed closely by golfers and skiers! They have to have
everything the top Pros use (and are paid to use). They are the
Marketoids wet dream!
We used to call this the "coozhe effect" as in creaming ones jeans over
the latest cycling product....
Riders like Eddy Merckx and Bernard Thévenet won major races with
essentially off-the-shelf Peugeot PX10s.... It's the motor not the
machine! One less beer or burrito will far exceed the benefits of
ceramic bearings!
Ceramic ball bearings provide thermal dimensional stability at the
temperatures created at high RPMs (usually 20,000+) in precision high
speed machinery. For example, high speed CNC wood and plastic cutting
routers and CNC milling machines that run over 20,000 RPM.
While there are some tough new ceramic materials that are very shock
resistant, ceramics are still prone to failure caused by vibrations,
especially at low frequencies.
Short of world record attempts all the testing data from SKF in pure
hype! At some time in the future with further ceramic material
improvements and reductions in manufacturing costs, ceramic bearing for
cycling may become cost effective.
Until then, the difference in cycling efficiency between 0.6W and 0.02W
is less than one good beer fart! ;-)
Chas.
* * Chas
> >On Fri, 14 Jul 2006 15:57:41 -0400, pinnah
> ><pinna...@THIS.comcast.net> wrote:
> >>Is it because the bearings themselves are so much better? Again, is
> >>there such a thing as a DuraAce ball bearing?
>
> carl...@comcast.net wrote:
> >You may be thinking of stuff like this:
> >
> >2006 FSA Ceramic Hub Bearing Set for Mavic & Zipp Wheelsets $339.99
> >Item: FSA152
>
> That's very interesting (and expensive).
>
> But the FSA bearings are cartridge style and only available for Campy
> type hubs, correct?
>
> Can loose ceramic balls be used with traditional cup/cone hubs?
> Are they available?
>
Yes you can buy loose ceramic ball bearings and put them in your Campy
hubs but they will probably chip or shatter on the first road impact if
not before while adjusting the cones.
http://www.bocabearings.com/main1.aspx?p=docs&id=20
Better yet, how about some ruby balls! The hardness and thermal
stability of ruby is next to that of diamond.
Even better, how about 1 less beer or burrito! ;-)
* * Chas
<b...@mambo.ucolick.org> wrote in message
news:1152930371.2...@m79g2000cwm.googlegroups.com...
The major benefit of ceramic bearings is thermal dimensional stability
caused by friction generated heat at high rotational speeds (20,000+
RPM).
One good beer fart would far exceed these hyped test results and if you
lit it off, the JATO effect could push you over the finish line ahead of
the competition during a heated sprint. Would that classify as doping?
;-)
Chas.
* * Chas
> Is there any meaningful difference in the rolling resistance between
> the 3 primary lines of hubs in the Shimano line?
>
> My cheap-skate dirt-bag opinion has always been that above the worst
> of the hubs, you mostly pay for a) better polish and bling and b)
> lower weight but that rolling resistance was largely the same.
>
> If you think there is less rolling resistance in the top end hubs, can
> you explain why and how this achieved?
>
> Is it because in the inner surface of the bearing cup is so much
> better?
>
> Is it because the cones are so much better? Is there such a thing as
> a DuraAce cone that differs in any way from, say, a 105 cone?
>
> Is it because the bearings themselves are so much better? Again, is
> there such a thing as a DuraAce ball bearing?
>
> Many thanks,
>
> -Dave
Years ago I built cyclocross wheels using Shimano 600 LF hubs. I used to
use these cheaper hubs because they where slightly beefier than DA or
Campy hubs and at 1/2 the price I never worried about trashing them.
The cones, cups and axles were made from the same alloy steels as the DA
hubs but the bearing surfaces were rough ground vs. the polished areas
on DA and Campy hubs.
I recently checked out a set of these wheels that survived years of off
road trashing. There was little or no wear or pitting in the bearings
but they spun just as rough as when they were new. Compared to some
Campy LF NR hubs from the same era, the Campys still run glass smooth.
I wouldn't use these cheaper hubs on the road but for off road riding I
don't think that it makes much difference.
Chas.
bfd
"* * Chas" <dna...@aol.spam.com> wrote in message
news:rdadnb3uk9Xt1CTZ...@comcast.com...
that came with Shimano Exage hubs, probably one of the lowest level of
Shimano hubs made. For commuting this bike makes sense as if it gets stolen
or damage, no big deal. However, one of the first things I did was open up
the hub and replace the bearing with Grade 25 bearings. I noticed that
although the race didn't look too bad, the cone was pure crap. Even though
the bike had very little miles on it, the cone was not polished and seem
really rough.
I've now put approximately 600-700 miles on this bike, not much, but this is
in wet/foggy weather on really bad (i.e., pothole filled) streets. The hubs
still spin smooth and quiet as new.
The main difference between DA/Ultegra and lower level shimano hubs are the
finish and weight. If you NEED low weight, then DA or ultegra is what you
should get. Otherwise, basically any shimano hub should provide years of
service.
Its pretty difficult to beat low end Shimano. Don't believe it? Then go ask
Miche, Gipiemme, Zeus, Galli, Ofmega, Malliard/Normandy/Atom, Avocet,
Suntour, Suzue, and Maxicar to name a few mfrs who were either put out of
business or no longer a viable competitor in the lucrative US market by one
mfr - Shimano.
David L. Johnson
> BULLPUCKY!
>
> Cyclists tend to be the most gullible group of consumers in the sports
> market place - followed closely by golfers and skiers! They have to have
> everything the top Pros use (and are paid to use). They are the
> Marketoids wet dream!
I agree with this.
>
> We used to call this the "coozhe effect" as in creaming ones jeans over
> the latest cycling product....
>
> Riders like Eddy Merckx and Bernard Thvenet won major races with
> essentially off-the-shelf Peugeot PX10s....
Um, no. Mercks's "Peugeot" was a Masi with a paint job. I recall a
picture out of one of his Tours, and it was clear that the Peugeot lugs
were painted over Masi lugs, and that the chainstays were the trademark
flat Masi stays.
--
David L. Johnson
__o | Deserves death! I daresay he does. Many that live deserve
_`\(,_ | death. And some that die deserve life. Can you give it to
(_)/ (_) | them? Then do not be too eager to deal out death in judgement.
-- J. R. R. Tolkein
carl...@comcast.net
<david....@lehigh.edu> wrote:
>On Sat, 15 Jul 2006 12:27:28 -0700, * * Chas wrote:
>
>> BULLPUCKY!
>>
>> Cyclists tend to be the most gullible group of consumers in the sports
>> market place - followed closely by golfers and skiers! They have to have
>> everything the top Pros use (and are paid to use). They are the
>> Marketoids wet dream!
>
>I agree with this.
>>
>> We used to call this the "coozhe effect" as in creaming ones jeans over
>> the latest cycling product....
>>
>> Riders like Eddy Merckx and Bernard Thvenet won major races with
>> essentially off-the-shelf Peugeot PX10s....
>
>Um, no. Mercks's "Peugeot" was a Masi with a paint job. I recall a
>picture out of one of his Tours, and it was clear that the Peugeot lugs
>were painted over Masi lugs, and that the chainstays were the trademark
>flat Masi stays.
Dear David,
Next you'll be spoiling movies for me by pointing out that the German
tanks are almost always U.S. tanks with a quick paint job. (Hard to
find genuine Wermacht rolling stock after 1945.)
But keep it up--I love reading about re-badging. It's a good way to
keep perspective on how important all the finicky little details here
on RBT really are.
Merckx probably could have switched to any frame used in the Tour that
year and won, but it's interesting that he preferred a Masi enough to
re-paint it.
I can't find a picture or explanation of the flat Masi chain stays. Do
you have anything about that feature?
Cheers,
Carl Fogel
David L. Johnson
> On Sat, 15 Jul 2006 19:49:34 -0500, "David L. Johnson"
> <david....@lehigh.edu> wrote:
>
>>On Sat, 15 Jul 2006 12:27:28 -0700, * * Chas wrote:
>>
>>> BULLPUCKY!
>>>
>>> Cyclists tend to be the most gullible group of consumers in the sports
>>> market place - followed closely by golfers and skiers! They have to have
>>> everything the top Pros use (and are paid to use). They are the
>>> Marketoids wet dream!
>>
>>I agree with this.
>>>
>>> We used to call this the "coozhe effect" as in creaming ones jeans over
>>> the latest cycling product....
>>>
>>> Riders like Eddy Merckx and Bernard Thvenet won major races with
>>> essentially off-the-shelf Peugeot PX10s....
>>
>>Um, no. Mercks's "Peugeot" was a Masi with a paint job.
Oops, Merckx's...
> Next you'll be spoiling movies for me by pointing out that the German
> tanks are almost always U.S. tanks with a quick paint job. (Hard to
> find genuine Wermacht rolling stock after 1945.)
I don't know about tanks.
> Merckx probably could have switched to any frame used in the Tour that
> year and won, but it's interesting that he preferred a Masi enough to
> re-paint it.
>
> I can't find a picture or explanation of the flat Masi chain stays. Do
> you have anything about that feature?
Just memory. Most chainstays of the time were crimped to make room on the
inside for the tire, and on the outside of the right side for the
chainrings. Masi's weren't; instead, the tubes were flattened to make
them thin enough --- closer to modern practice than the crimping of old,
which is probably a stress problem.
You can see some pictures of a '68 Masi with this on
http://hometown.aol.com/bobhoveyga/myhomepage/Bicycles/68MasiSpec/index.htm
which I just found by starting at Classic Rendezvous. One of the pictures
on that page clearly shows the flat chainstay. Oddly, it also seems to
show a Simplex derailleur.
Some earlier models shown on Classic Rendezvous don't show these stays,
but I do recall them in the late '60s, when I greatly lusted after that
bike.
--
David L. Johnson
__o | Anyone who is capable of getting themselves made President
_`\(,_ | should on no account be allowed to do the job. -- Douglas Adams
(_)/ (_) |
carl...@comcast.net
<david....@lehigh.edu> wrote:
Dear David,
Yes, both sides get much thinner or flatter or whatever they did:
http://hometown.aol.com/bobhoveyga/myhomepage/Bicycles/68MasiSpec/images/MS06.jpg
As for the Simplex derailleur, the text at the top of your link says:
"An odd mix of components for a Masi, I wonder if perhaps the former
owner's family had a feud going on with the Campagnolo clan. Not a
single Campy part. Well, the hubs are Campy but they are dated '72
and not original to the bike (the bars and stem appear to be later
additions as well)."
Thanks,
Carl Fogel
* * Chas
"David L. Johnson" <david....@lehigh.edu> wrote in message
news:13KdncljQf2...@ptd.net...
> On Sat, 15 Jul 2006 12:27:28 -0700, * * Chas wrote:
>
> > BULLPUCKY!
> >
> > Cyclists tend to be the most gullible group of consumers in the
sports
> > market place - followed closely by golfers and skiers! They have to
have
> > everything the top Pros use (and are paid to use). They are the
> > Marketoids wet dream!
>
> I agree with this.
> >
> > essentially off-the-shelf Peugeot PX10s....
>
> Um, no. Mercks's "Peugeot" was a Masi with a paint job. I recall a
> picture out of one of his Tours, and it was clear that the Peugeot
lugs
> were painted over Masi lugs, and that the chainstays were the
trademark
> flat Masi stays.
>
David,
If it looks like a duck... quacks like a duck.... White frame, black
trim, Nervex lugs, Stronglight 93 cranks, Mafac brakes, Simplex
derailleurs, Normandy hubs, Ideale seat and so on.....
Here's a classic picture of Eddy and his ersatz PX-10. The picture below
Eddy's shows Bernard Thévenet riding a PY-10:
http://www.classicrendezvous.com/France/Peugeot/PX10_history.htm
Merckx Team Faema bikes were definately Masi's. A friend of mine has one
of the team bikes from that era - last picture at the bottom of the web
page:
http://www.bikecult.com/works/archive/04bicycles/pjohnsonJB04.html
I guess that by the time Merckx joined the Molteni team he was ridding
Colnagos.
We had one of Luis Ocaña's 1973 TDF Gitanes at our shop. It was just a
plain French factory bike, nothing special. I think that it was all
Campy equipped.
Ocaña also rode a titanium Speedwell in the mountains when he won the
TDF that year.
It all gets back to the motor over the machine doesn't it?
Chas.
* * Chas
"bfd" <bfd...@comcast.net> wrote in message
news:VfCdndxQocELzSTZ...@comcast.com...
building those wheels, Shimano only had the 600 series and DuraAce
series for better quality components. All the rest of their product line
was aimed at department store bikes.
There was a drastic difference in the quality of the grinds in the cups
and cones between the DA and 600 hubs. The DuraAce hubs had a polished
finish, at least an 8 RMS. The finish on the 600 bearing surfaces was a
32 RMS or rougher. The rough bearing surfaces will cause premature ball,
cup and race failure as compared to a polished surface like the DA's
plus they also have higher rolling resistance.
I didn't disassemble the wheels that I checked but I was surprised at
how smooth they spun considering that the grease was over 10 years old
and probably hardened plus these wheels had been used off road in mud,
water and dust. I didn't detect any pits in the bearings when I spun
them but they were nowhere as smooth as in a better quality hub.
That's testimony to the quality of material used by Shimano in the
bearings on those hubs. On the other hand, precision sealed bearings
would only add a few dollars to the manufacturing costs and pretty much
alleviate the need for rebuilding hubs.
Chas.
Qui si parla Campagnolo
pinnah wrote:
> Is there any meaningful difference in the rolling resistance between
> the 3 primary lines of hubs in the Shimano line?
No
>
> My cheap-skate dirt-bag opinion has always been that above the worst
> of the hubs, you mostly pay for a) better polish and bling and b)
> lower weight but that rolling resistance was largely the same.
>
> If you think there is less rolling resistance in the top end hubs, can
> you explain why and how this achieved?
Harder bearing balls, shinnier cone and cup surfaces. BUT 'high' end
hubs are often sealed cartridge bearings, which have lots of 'rolling
resistence' due to the rubber seals.
>
> Is it because in the inner surface of the bearing cup is so much
> better?
>
> Is it because the cones are so much better? Is there such a thing as
> a DuraAce cone that differs in any way from, say, a 105 cone?
>
> Is it because the bearings themselves are so much better? Again, is
> there such a thing as a DuraAce ball bearing?
Not really-for Campag and shimano, mostly bragging rights and in the
case of 10s DA, lighter, much different design but still cup and cone,
the way bicycle hibs ought ta be...
Qui si parla Campagnolo
Reality, what a concept.....more $ for gadgets when doing what Eddy
said so many times to make one a better cyclist-"ride lots"....
531Aussie
as an 80s guys, I just can't cross over to sealed hubs. I'm the only guy
around here under 40 who still races on cones and balls. :)
Also, how about cassette body rolling friction? I bought some new, old
stock 105 9sp hubs, and the barrel didn't spin very freely at all. The
shop guy said the grease that Shimano uses dries up after a while.
Barrel friction obviously doesn't matter when the cranks are moving,
but speed can be lost if coasting is inhibited
So, what about the 'coasting' resistance of different quality hub
bodies?
--
531Aussie
bfd
"531Aussie" <531Aussi...@no-mx.forums.cyclingforums.com> wrote in
message news:531Aussi...@no-mx.forums.cyclingforums.com...
>
> as an 80s guys, I just can't cross over to sealed hubs. I'm the only guy
> around here under 40 who still races on cones and balls. :)
>
"cones and balls."
carl...@comcast.net
Dear 531,
Well . . .
The shop guy may have forgotten that all grease eventually dries up,
not just Shimano's special secret anti-coasting compound.
For anyone worried about grease drag, the first trick is to clean and
re-grease the mechanism.
The second trick, if you're determined to win a coasting race at all
costs, might be to replace the grease with oil.
Depending on their mechanisms, desperate coasting competitors might
even remove a pawl.
Less competitive types will take comfort in the fact that while the
faint buzz of the ratchet mechanism signals a hideous friction loss,
the friction of both pulleys, both pedals, and the bottom bracket has
been eliminated.
(Not to mention the chain.)
In any case, serious coasting is usually performed downhill at speeds
where what reallly matters is weight and wind drag, not the extremely
tiny drag of the pawls and grease that allow coasting.
And coasting downhill ever so slightly faster rarely matters. In real
life, it's usually how you brake through the corners on the downhill,
not whether your maximum speed was 0.01 mph higher in the straight.
Even worse, downhill is unlikely to win any real race. If a fellow
climbs a 10-mile pass at 15 mph, 1 mph faster than you do at 14 mph,
he reaches the top in 40 minutes, 2400 seconds.
While you still toil toward the top, he turns around and descends at
30 mph, reaching the bottom 10 miles away in 20 minutes, 1200 seconds.
At only 14 mph, you reach the top 2:51.4 behind him, turn, and
desperately try to coast down fast enough to overtake him.
Good luck. You have to average 35 mph downhill to his 30 mph just to
tie at the bottom. Few riders can manage an extra 5 mph against
reasonable competition just by better braking and cornering, much less
superior grease and coasting efficiency.
Cheers,
Carl Fogel
Phil Lee, Squid
Interesting... I had thought that I could make up the uphills on the
downhills during MTB racing, but I guess that's not the case.
--
Phil Lee, Squid
carl...@comcast.net
Dear Phil,
It's one of those hideous laws of the universe.
Barring weird situations, bicycling is basically a slow-motion drag
race in which the engine counts far more than anything else.
The section where you spend the most time is the section where even a
small difference becomes crucial--and uphill takes far more time than
downhill in typical bicycling. Even worse, we all use roughly the same
engine for downhill (gravity versus wind drag), so that difference is
largely eliminated in downhill.
Good descenders are often fooled by the illusion of apparently huge
leads. On a long, twisty downhill, they really can leave slower riders
so far behind that they're out of sight.
If they were going uphill at 10 mph, that would be a huge lead.
But going dowhill at 40 mph, it's not really impressive.
True, the slower rider may be a whopping quarter-mile behind the fast
descender at the bottom and completely out of sight, but he'll still
arrive only 22.5 seconds later.
The Tour is won by climbing and ITT, where the human engine counts,
not by superb cornering and braking.
The same is true for MTB racing. It's how fast your legs get you to
the top, which is the longest and slowest part of the race, not how
fast you zip back down over the bumps and corners--they don't last
long enough to let you overtake the fast climbers.
Cheers,
Carl Fogel
Qui si parla Campagnolo
531Aussie wrote:
> as an 80s guys, I just can't cross over to sealed hubs. I'm the only guy
> around here under 40 who still races on cones and balls. :)
>
> Also, how about cassette body rolling friction? I bought some new, old
> stock 105 9sp hubs, and the barrel didn't spin very freely at all. The
> shop guy said the grease that Shimano uses dries up after a while.
> Barrel friction obviously doesn't matter when the cranks are moving,
> but speed can be lost if coasting is inhibited
shimano freehubs are really just a freewheel, with two rows of 1/8inch
bearings, not very high quality races and cones, bolted onto a hub
body. Not 'grease' in there, or shouldn't be, should be oiled but these
have never been really smooth...
>
> So, what about the 'coasting' resistance of different quality hub
> bodies?
All are like above or cartridge bearings around the axle that is
supported at the right hub flange. Some are smoother than others but
coasting for a freehub or freewheel is about the same. Hubs,
particulalry cart bearing ones, are sluggish, with seal dragf,
generally but the amount of energy required or loss because of it is
teeny.
BUT track guys still oil their hubs and BBs...for that special
event...not grease and not cart bearings...for genuine pro track guys
not weekend warriors.
>
>
> --
> 531Aussie
531Aussie
Qui si parla Campagnolo Wrote:
> All are like above or cartridge bearings around the axle that is
> supported at the right hub flange. Some are smoother than others but
> coasting for a freehub or freewheel is about the same. Hubs,
> particulalry cart bearing ones, are sluggish, with seal dragf,
> generally but the amount of energy required or loss because of it is
> teeny.
>
> BUT track guys still oil their hubs and BBs...for that special
> event...not grease and not cart bearings...for genuine pro track guys
thanks
--
531Aussie
John Dacey
On 17 Jul 2006 06:18:47 -0700, "Qui si parla Campagnolo" wrote:
>BUT track guys still oil their hubs and BBs...for that special
>event...not grease and not cart bearings...for genuine pro track guys
>not weekend warriors.
I do a lot of track work here and my experience is not consistent with
your claim.
At elite levels, the wheels most often seen in track racing (Mavic's
Comete Piste and Io; Corima's track disc and three and four spoke
composites; Zipp's disc and 404 track wheels) all are fitted with
cartridge bearings. Similarly, the dedicated bottom brackets for track
crank models from Campagnolo, Shimano, Miche and some others have used
cartridge bearings for years now. Most contemporary track componentry
simply doesn't lend itself to the kind of rituals and affectations you
seem to think is common practice.
Of course there will always be a small fraction of track racers who
obsess over minutia, but it would be wrong to think that their number
is greater by percentage than that of road or mountain bike racers who
similarly indulge themselves thus.
-------------------------------
John Dacey
Business Cycles, Miami, Florida
Since 1983
Our catalog of track equipment: online since 1996
305-273-4440
http://www.businesscycles.com
-------------------------------
Qui si parla Campagnolo
John Dacey wrote:
> "Laudator temporis acti." - Horace
> On 17 Jul 2006 06:18:47 -0700, "Qui si parla Campagnolo" wrote:
>
> >BUT track guys still oil their hubs and BBs...for that special
> >event...not grease and not cart bearings...for genuine pro track guys
> >not weekend warriors.
>
> I do a lot of track work here and my experience is not consistent with
> your claim.
>
> At elite levels, the wheels most often seen in track racing (Mavic's
> Comete Piste and Io; Corima's track disc and three and four spoke
> composites; Zipp's disc and 404 track wheels) all are fitted with
> cartridge bearings. Similarly, the dedicated bottom brackets for track
> crank models from Campagnolo, Shimano, Miche and some others have used
> cartridge bearings for years now. Most contemporary track componentry
> simply doesn't lend itself to the kind of rituals and affectations you
> seem to think is common practice.
>
> Of course there will always be a small fraction of track racers who
> obsess over minutia, but it would be wrong to think that their number
> is greater by percentage than that of road or mountain bike racers who
> similarly indulge themselves thus.
So when I said 'track guys still oil their hubs and BBs', I don't
remember mentioning percnetages, or numbers or such...lessee....nope,
re-read it and no numbers of those that do, just that some still do,
from the boys at EA, where there actually is a velodrome, in LA...
Phil Lee, Squid
To add another data point, I've never passed anyone on the uphills... only
the downhills.
--
Phil Lee, Squid
Bill Sornson
> To add another data point, I've never passed anyone on the uphills...
> only the downhills.
Back when I used to run, I actually passed someone once.
{pause}
She was on crutches, but I got by her gosh darn it... (The white cane
almost tripped me up, though!)
Lightning Louie
john
> On Fri, 14 Jul 2006 15:57:41 -0400, pinnah
> <pinna...@THIS.comcast.net> wrote:
>
Dear Carl
Thank you so very much for this astonishing contribution to the
advancement of bicycling. However even you haven't realized the true
significance of this.
The truth of the above 'data' becomes blindingly clear when standard
statistical analysis is applied, of cubing the improvements & dividing
by the square root. In reality the rider starts to accelerate
negatively, eventually reaching hyper warp & disappears into a wormhole
to another dimension, basackwrds ;-)
You dirty troll!
pinnah
>> road trashing. There was little or no wear or pitting in the bearings
>> but they spun just as rough as when they were new. Compared to some
>> Campy LF NR hubs from the same era, the Campys still run glass smooth.
"bfd" <bfd...@comcast.net> wrote:
>I disagree.
[snip...]
>I've now put approximately 600-700 miles on this bike, not much, but this is
>in wet/foggy weather on really bad (i.e., pothole filled) streets. The hubs
>still spin smooth and quiet as new.
Guys, thanks for the direct (but seemingly less entertaining)
responses!
Some follow ups....
Is there any correspondance between the roughness of a race and
rolling resistance? Does roughness affect longevity?
Regarding the grade 25 bearings, what benifits do they provide? Better
durability? Lower rolling resistance?
Many thanks,
pinnah
>> Is there any meaningful difference in the rolling resistance between
>> the 3 primary lines of hubs in the Shimano line?
>
"Qui si parla Campagnolo" <pe...@vecchios.com> wrote:
>No
>> If you think there is less rolling resistance in the top end hubs, can
>> you explain why and how this achieved?
>
>Harder bearing balls, shinnier cone and cup surfaces. BUT 'high' end
>hubs are often sealed cartridge bearings, which have lots of 'rolling
>resistence' due to the rubber seals.
Very helpful. Many thanks!
carl...@comcast.net
Dear Dave,
Grade 25 bearings are ridiculous--they're ridiculously hard, round,
uniform, and cheap.
There's simply no reason to buy anything cheaper, and no apparent
bicycle-drag advantage to trying to buy anything more expensive.
You won't get a $340 drag advantage from a set of ceramic bearings.
http://draco.acs.uci.edu/rbfaq/FAQ/8f.7.html
As for rolling resistance, a rougher road surface affects the
comparatively huge rolling resistance of the tire far more than the
tiny bearing drag. For all practical purposes, bearing drag is ignored
in bicycle power and speed calculations.
Flip your bike upside down, attach a speedometer to the rear wheel,
and crank it up to 30 mph. Stop and time how long it takes the rear
wheel to stop against the wind drag on the spokes and tire, the
freewheeling pawls, and the bearing drag.
Roughly 99.9% of that drag is wind drag and pawls. If you remove the
pawls and repeat the experiment in an evacuated bell jar, the wheel
will probably still be spinning the next day.
The chief drag of a bearing is its rubber seals, not bearing itself.
Cheers,
Carl Fogel
jim beam
and even that decreases to a minimal amount once the bearing is actually
turning at speeds greater than the casual mechanic's finger twist.