Ceramic bearings

Qui si parla Campagnolo wrote:
On Jul 11, 6:59 am, jim beam wrote:
Qui si parla Campagnolo wrote:



On Jul 10, 10:24�pm, wrote:
An email just asked me if I was as skeptical about ceramic bearings as
I am of the "noticeably robust forward thrust" produced by a 4% change
in total bike and rider weight.
Ah, the joys of being known as doubtful!
The email helpfully linked to this ceramic bearing review, which is
pretty exciting:
"What we received from Ceramic Speed was a bottom bracket, wheel
bearings, and pulleys. Once we were able to have them installed on the
Bicycle.net road bike the difference was immediate."
"To start, we spun the wheels and they just kept spinning and
spinning. It was impressive how smooth the bearings were. Once we took
the bike on the road and got in some rides we got the feeling like the
bike just wanted to keep accelerating. There was an obvious reduction
in overall friction giving the rider that added boost of speed."
"In the end we are sold at Bicycle.net on the improvement Ceramic
Speed bearings will make in the bike�s overall performance. We
contacted Ceramic Speed for more details on our perceived improvement
and they claim that the power savings is up to 10-12 watts . . ."
�http://www.bicycle.net/2008/ceramic-speed-bearings
Well . . .
I'm _more_ skeptical of the ceramic bearing claims.
After all, a 4% weight reduction can actually shave 2% off someone's
time on a climb.
But the bearing claim looks implausible from the start.
If we assume a 95% efficient transmission, then putting 300 watts into
the pedals would produce only 285 watts at the tire, a loss of only 15
watts.
It's hard to imagine the bottom bracket, wheel bearings, and two
pulleys accounting for 10 to 12 watts of the total 15 watts lost,
since there are also the pedal bearings (somehow they were forgotten)
and the chain rollers engaging and disengaging from each sprocket
under load.
But let's go along with the fantasy that sprinkling some ceramic
bearings designed for 20,000 RPM applications into a low-RPM bicycle
transmission will save 10-12 watts for our test rider.
Will a rider experience "the feeling like the bike just wanted to keep
accelerating"?
Will he notice "an obvious reduction in overall friction giving the
rider that added boost of speed"?
Well, yes, for values of acceleration and top speed that increase by
about 1%.
Here's a familiar side-by-side bike speed calculator:
�http://bikecalculator.com/veloUS.html
Use on-the-drops and tubulars for both bikes, then crank one up to 300
watts and give give the other that extra alleged 12 watts:
� � � � � � �mph
300 watts �25.08
312 watts �25.44
That's a sizzling 0.36 mph faster, a 1.43% speed increase. You could
see it on a cyclocomputer as you pedalled, but the display would be
jumping around from 25.1 to 25.4 mph anyway on any normal road.
On a 20-mile ride, the alleged 12 watt improvement will produce a
41-second lead in 47 minutes, about 1.4% faster.
Let's try a sprint calculator:
�http://www.analyticcycling.com/DiffE...ions_Page.html
With the defaults, 45.2 seconds for a 500 meter standing start.
Raise the maximum power and average power 12 watts, and time drops to
44.7 seconds, just over 1% faster.
Set the average power to one watt less than the maximum power, 662
max/661 avg versus 650 max/649 avg, and the times drop to 38.6 versus
38.9 seconds, a 0.3 second difference, just under 1% faster.
So rounding probably exaggerates or minimizes the tiny ~1% difference
in sprint calculations. Not exactly something that a rider could
"feel".
Anyway, I doubt that the ceramic bearings put an extra 12 watts into
the rear tire in the first place.
And even if they did, I doubt that any rider could sense the
difference, much less perceive it as the dramatic improvement promised
by the marketing department.
Cadel Evans apparently runs ceramic pulley bearings:
http://www.cyclingnews.com/road/2008...e.php?id=/phot...
But he doesn't bother with ceramic rear hub bearings:
http://www.cyclingnews.com/road/2008...e.php?id=/phot...
That's an odd choice.
Do ceramic bearings in two deraileur pulleys (which handle only the
tension and power of the nearly slack lower chain run) provide a
bigger payoff than ceramic bearings in the rear axle (which handles
over half the weight and all the power of the rider)?
Maybe ceramic bearings don't make any practical difference, even to a
Tour de France rider?
Cheers,
Carl Fogel
How dare you sully up this discussion with facts!!
Ceramic bearings are one of the biggest hypes put onto the bike biz
since biopace.
I just saw an add for a complete set of 5/32 ceramic balls for Campag
wheels. 60 balls for only $330......$5.50 per ball..YGBSM....
ceramic bearing balls do in fact cost a good deal more to produce than
steel ones. and their precision, fwtw, it typically about 10 times
better. how much is a single steel bearing ball?

grade 25, we sell for $.10 per ball..for bicycles, more than adequate.
So, ceramic is 55 times more expensive for 10 times rounder.

genuine campy are more like $0.80 each. so ceramic is only 6.9 times
more expensive for 10 times rounder...

On Fri, 11 Jul 2008 05:59:32 -0700
jim beam wrote:

SNIP

I just saw an add for a complete set of 5/32 ceramic balls for
Campag wheels. 60 balls for only $330......$5.50 per ball..YGBSM....

ceramic bearing balls do in fact cost a good deal more to produce
than steel ones. and their precision, fwtw, it typically about 10
times better. how much is a single steel bearing ball?


I pay 2.5 AU cents a 1/4" bearing. The original review reminded me of a
couple of articles a co-worker of mine wrote for the local bicycle rag
on chain lubes and a black(!!) hi-visibility back-pack cover for
cyclists.

Every negative thing she wrote about the products was edited out and
replace with praise.

Cheers

Joel

"A Muzi" wrote in message ...
| -snip bearings-
| Qui si parla Campagnolo wrote:
| grade 25, we sell for $.10 per ball..for bicycles, more than adequate.
| So, ceramic is 55 times more expensive for 10 times rounder.
|
| Every product has a high-end price parabola. One is tempted to ask
| about cost/benefit or where adequate features for the intended purpose
| are optimized. In a jet engine, ceramic balls may represent a cost
| savings over the unit's life. Hard to justify in our hubs, cranks etc.
| --
| Andrew Muzi

The ultimate is the customer who wants ceramic balls in his headset. Talk about the opposite of high-rpm...

--Mike-- Chain Reaction Bicycles
www.ChainReactionBicycles.com

On Fri, 11 Jul 2008 23:19:42 -0700, "Mike Jacoubowsky"
wrote:

"A Muzi" wrote in message ...
| -snip bearings-
| Qui si parla Campagnolo wrote:
| grade 25, we sell for $.10 per ball..for bicycles, more than adequate.
| So, ceramic is 55 times more expensive for 10 times rounder.
|
| Every product has a high-end price parabola. One is tempted to ask
| about cost/benefit or where adequate features for the intended purpose
| are optimized. In a jet engine, ceramic balls may represent a cost
| savings over the unit's life. Hard to justify in our hubs, cranks etc.
| --
| Andrew Muzi

The ultimate is the customer who wants ceramic balls in his headset. Talk about the opposite of high-rpm...

--Mike-- Chain Reaction Bicycles
www.ChainReactionBicycles.com

Dear Mike & Andrew,

Does anyone sell ceramic bearings for pedals?

Come to think of it, what about cartridge bearings for pedals?

Cheers,

Carl Fogel

| -snip bearings-
| Qui si parla Campagnolo wrote:
| grade 25, we sell for $.10 per ball..for bicycles, more than adequate.
| So, ceramic is 55 times more expensive for 10 times rounder.

"A Muzi" wrote
| Every product has a high-end price parabola. One is tempted to ask
| about cost/benefit or where adequate features for the intended purpose
| are optimized. In a jet engine, ceramic balls may represent a cost
| savings over the unit's life. Hard to justify in our hubs, cranks etc.

"Mike Jacoubowsky" wrote:
The ultimate is the customer who wants ceramic balls in his headset. Talk about the opposite of high-rpm...

wrote:
Does anyone sell ceramic bearings for pedals?
Come to think of it, what about cartridge bearings for pedals?

Ceramic are obviously available for loose-ball pedals, ceramic
cartridges maybe (size?), Bremen cups no. The trend is to sintered
bronze sleeves, akin to an electric motor journal.

The same ceramic balls for your 2008 Record hubs fit most classic pedals
along the lines of an MKS Sylvan; more modern designs are seldom loose-ball
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971
** Posted from http://www.teranews.com **

Carl Fogel wrote:

Come to think of it, what about cartridge bearings for pedals?

A very common arrangement with clipless pedals these days is to have a
plain Oilite beaing on the inboard end of the spindle, and a very
small cartridge bearing (6mm bore) on the outboard end.

My last experiment with clipless pedals was with plastic-bodied Time
ATACs. I chose these because they used a cartridge bearing at each
end, and the spindle diameter at the inboard bearing was 12mm. In
order to get the comparatively generous spindle and bearing sizes, I
was willing to accept the plastic bodies.

Atomlab (a BMX parts manufacturer) for years has made pedals featuring
"DU" bearings. I thought at first that they meant bearings made from
depleted uranium, but fortunately that isn't the case. DU is a type
of plain bearing with a steel shell bonded to a layered amalgam of
Babbitt-type material sintered together with PTFE and other solid dry
lubricants. The advantage of plain bearings in a freestyle pedal is
that they allow a pedal with a thick spindle to have a relatively thin
body.

http://atomlab.com/pedals.html

Chalo

On Sat, 12 Jul 2008 09:51:42 -0500, A Muzi
wrote:

| -snip bearings-
| Qui si parla Campagnolo wrote:
| grade 25, we sell for $.10 per ball..for bicycles, more than adequate.
| So, ceramic is 55 times more expensive for 10 times rounder.

"A Muzi" wrote
| Every product has a high-end price parabola. One is tempted to ask
| about cost/benefit or where adequate features for the intended purpose
| are optimized. In a jet engine, ceramic balls may represent a cost
| savings over the unit's life. Hard to justify in our hubs, cranks etc.

"Mike Jacoubowsky" wrote:
The ultimate is the customer who wants ceramic balls in his headset. Talk about the opposite of high-rpm...

wrote:
Does anyone sell ceramic bearings for pedals?
Come to think of it, what about cartridge bearings for pedals?

Ceramic are obviously available for loose-ball pedals, ceramic
cartridges maybe (size?), Bremen cups no. The trend is to sintered
bronze sleeves, akin to an electric motor journal.

The same ceramic balls for your 2008 Record hubs fit most classic pedals
along the lines of an MKS Sylvan; more modern designs are seldom loose-ball

Dear Andrew,

Yikes! I googled and found ceramic cartridge bearings for pedals:
http://www.glorycycles.com/fsacecabefor.html

They cost only $139.90, a small price to pay for going . . .

Er, the PDF seems very confused about how much faster we'll be going.
http://lib.store.yahoo.net/lib/glorycycles/fsacer.pdf

First the PDF claims that using ceramic bearings can save "22m in just
55 seconds at 32kph. In short, astounding speed improvement of 4%."

In other words, you might go 33.28 kmh instead of 32.0 kmh, 4% faster.

But then the PDF claims that a "Record BB @ 100rpm and 400W consumes
0.6W, the same BB with ceramic bearings consumes 0.02W."

Let's round the ceramic drag down to zero and use this calculator:
http://bikecalculator.com/veloMetric.html

Tubulars, on-the-drops watts km/h
Record BB bearings 400.0 44.94
magic ceramic bearings 400.6 44.97 0.067% faster

Hmmm . . . a 0.067% speed increase is only about one-sixtieth of the
astounding 4% speed increase that we were promised.

To go 4% faster than 44.94 kmh speed with 400 watts, we need to go
46.74 kmh with . . .

This calculator tells us how many watts we need for 46.74 kmh:
http://bikecalculator.com/wattsMetric.html

We need 447 watts to go 4% faster than we went at 400 watts.

It's darned hard to get 47 extra watts by sprinkling ceramic bearings
in the transmission if the bottom bracket uses only 0.6 watts.

So I may wait a bit before I order those $140 ceramic cartridge pedal
bearings.

Cheers,

Carl Fogel

On Jul 13, 3:09 am, wrote:
On Sat, 12 Jul 2008 09:51:42 -0500, A Muzi
wrote:



| -snip bearings-
| Qui si parla Campagnolo wrote:
| grade 25, we sell for $.10 per ball..for bicycles, more than adequate.
| So, ceramic is 55 times more expensive for 10 times rounder.

"A Muzi" wrote
| Every product has a high-end price parabola. One is tempted to ask
| about cost/benefit or where adequate features for the intended purpose
| are optimized. In a jet engine, ceramic balls may represent a cost
| savings over the unit's life. Hard to justify in our hubs, cranks etc.

"Mike Jacoubowsky" wrote:
The ultimate is the customer who wants ceramic balls in his headset. Talk about the opposite of high-rpm...

wrote:
Does anyone sell ceramic bearings for pedals?
Come to think of it, what about cartridge bearings for pedals?

Ceramic are obviously available for loose-ball pedals, ceramic
cartridges maybe (size?), Bremen cups no. The trend is to sintered
bronze sleeves, akin to an electric motor journal.

The same ceramic balls for your 2008 Record hubs fit most classic pedals
along the lines of an MKS Sylvan; more modern designs are seldom loose-ball

Dear Andrew,

Yikes! I googled and found ceramic cartridge bearings for pedals:
http://www.glorycycles.com/fsacecabefor.html

They cost only $139.90, a small price to pay for going . . .

Er, the PDF seems very confused about how much faster we'll be going.
http://lib.store.yahoo.net/lib/glorycycles/fsacer.pdf

First the PDF claims that using ceramic bearings can save "22m in just
55 seconds at 32kph. In short, astounding speed improvement of 4%."

In other words, you might go 33.28 kmh instead of 32.0 kmh, 4% faster.

But then the PDF claims that a "Record BB @ 100rpm and 400W consumes
0.6W, the same BB with ceramic bearings consumes 0.02W."

Let's round the ceramic drag down to zero and use this calculator:
http://bikecalculator.com/veloMetric.html

Tubulars, on-the-drops watts km/h
Record BB bearings 400.0 44.94
magic ceramic bearings 400.6 44.97 0.067% faster

Hmmm . . . a 0.067% speed increase is only about one-sixtieth of the
astounding 4% speed increase that we were promised.

To go 4% faster than 44.94 kmh speed with 400 watts, we need to go
46.74 kmh with . . .

This calculator tells us how many watts we need for 46.74 kmh:
http://bikecalculator.com/wattsMetric.html

We need 447 watts to go 4% faster than we went at 400 watts.

It's darned hard to get 47 extra watts by sprinkling ceramic bearings
in the transmission if the bottom bracket uses only 0.6 watts.

So I may wait a bit before I order those $140 ceramic cartridge pedal
bearings.

Cheers,

Carl Fogel

Ceramic bearings sometimes be found much less expensively than the
prices quoted in these postings. It takes a different talent than CF's
calculations of cost/watt to explain why there isn't price competition
for these. Could be in their failure rate?

I don't know why 3 fine shop owners here disparage them. While there
may be no way to honestly tout them (except for wear in some
applications?) why not let the fool and his money soon be parted if
the client wants them (unless warrantee replacement is too
frequent)?

But, I'd really rather know why I can't find replacement pulley wheels
for less than the price of entire cheap rear ders. Wait, that
dastardly Chris at Velo-Orange has 'em for $4/pair.

But, we've been here before. Suntour put ball bearing cartridges in
their excellent rear ders long ago, then smartly sold the pulley
wheels separately as an upgrade. Not that they claimed the wheels with
those bearing is why their ders shifted better. But, if the consumer
wanted to respect ball bearings more and believe that Campy bronze
bushings were primitive, well Maeda industries was happy to make many
extra bucks on the upgrades. As were shops.

Harry Travis

On Jul 13, 2:29*am, "
wrote:
On Jul 13, 3:09 am, wrote:



On Sat, 12 Jul 2008 09:51:42 -0500, A Muzi
wrote:

| -snip bearings-
| Qui si parla Campagnolo wrote:
| grade 25, we sell for $.10 per ball..for bicycles, more than adequate.
| So, ceramic is 55 times more expensive for 10 times rounder.

"A Muzi" wrote
| Every product has a high-end price parabola. *One is tempted to ask
| about cost/benefit or where adequate features for the intended purpose
| are optimized. In a jet engine, ceramic balls may represent a cost
| savings over the unit's life. Hard to justify in our hubs, cranks etc.

*"Mike Jacoubowsky" wrote:
The ultimate is the customer who wants ceramic balls in his headset.. Talk about the opposite of high-rpm...

wrote:
Does anyone sell ceramic bearings for pedals?
Come to think of it, what about cartridge bearings for pedals?

Ceramic are obviously available for loose-ball pedals, ceramic
cartridges maybe (size?), Bremen cups no. The trend is to sintered
bronze sleeves, akin to an electric motor journal.

The same ceramic balls for your 2008 Record hubs fit most classic pedals
along the lines of an MKS Sylvan; more modern designs are seldom loose-ball

Dear Andrew,

Yikes! I googled and found ceramic cartridge bearings for pedals:
*http://www.glorycycles.com/fsacecabefor.html

They cost only $139.90, a small price to pay for going . . .

Er, the PDF seems very confused about how much faster we'll be going.
*http://lib.store.yahoo.net/lib/glorycycles/fsacer.pdf

First the PDF claims that using ceramic bearings can save "22m in just
55 seconds at 32kph. In short, astounding speed improvement of 4%."

In other words, you might go 33.28 kmh instead of 32.0 kmh, 4% faster.

But then the PDF claims that a "Record BB @ 100rpm and 400W consumes
0.6W, the same BB with ceramic bearings consumes 0.02W."

Let's round the ceramic drag down to zero and use this calculator:
*http://bikecalculator.com/veloMetric.html

Tubulars, on-the-drops *watts *km/h
* * Record BB bearings *400.0 *44.94
magic ceramic bearings *400.6 *44.97 *0.067% faster

Hmmm . . . a 0.067% speed increase is only about one-sixtieth of the
astounding 4% speed increase that we were promised.

To go 4% faster than 44.94 kmh speed with 400 watts, we need to go
46.74 kmh with . . .

This calculator tells us how many watts we need for 46.74 kmh:
*http://bikecalculator.com/wattsMetric.html

We need 447 watts to go 4% faster than we went at 400 watts.

It's darned hard to get 47 extra watts by sprinkling ceramic bearings
in the transmission if the bottom bracket uses only 0.6 watts.

So I may wait a bit before I order those $140 ceramic cartridge pedal
bearings.

Cheers,

Carl Fogel

Ceramic bearings sometimes be found much less expensively than the
prices quoted in these postings. It takes a different talent than CF's
calculations of cost/watt to explain why there isn't price competition
for these. Could be in their failure rate?

I don't know why 3 fine shop owners here disparage them. While there
may be no way to honestly tout them (except for wear in some
applications?) why not let the fool and his money soon be parted if
the client wants them (unless warrantee replacement is too
frequent)?

Well, this shop owner doesn't like to make promises he can't keep.
Even if they say they make no real difference, in fact, the customer
thinks they do. So, after lightening his wallet by hundreds of
dollars, he gets mad at me for STILL not being able to get up that
hill. Same for wheelsouttaboxes and many other things that most other
bike shops shill about.

But, I'd really rather know why I can't find replacement pulley wheels
for less than the price of entire cheap rear ders. Wait, that
dastardly Chris at Velo-Orange has 'em for $4/pair.

We have pulleys in the $10 per range, less than any rder.

But, we've been here before. Suntour put ball bearing cartridges in
their excellent rear ders long ago, then smartly sold the pulley
wheels separately as an upgrade. Not that they claimed the wheels with
those bearing is why their ders shifted better. But, if the consumer
wanted to respect ball bearings more and believe that Campy bronze
bushings were primitive, well Maeda industries was happy to *make many
extra bucks on the upgrades. As were shops.

Harry Travis

wrote:
On Jul 13, 3:09 am, wrote:
On Sat, 12 Jul 2008 09:51:42 -0500, A Muzi
wrote:



| -snip bearings-
| Qui si parla Campagnolo wrote:
| grade 25, we sell for $.10 per ball..for bicycles, more than adequate.
| So, ceramic is 55 times more expensive for 10 times rounder.
"A Muzi" wrote
| Every product has a high-end price parabola. One is tempted to ask
| about cost/benefit or where adequate features for the intended purpose
| are optimized. In a jet engine, ceramic balls may represent a cost
| savings over the unit's life. Hard to justify in our hubs, cranks etc.
"Mike Jacoubowsky" wrote:
The ultimate is the customer who wants ceramic balls in his headset. Talk about the opposite of high-rpm...
wrote:
Does anyone sell ceramic bearings for pedals?
Come to think of it, what about cartridge bearings for pedals?
Ceramic are obviously available for loose-ball pedals, ceramic
cartridges maybe (size?), Bremen cups no. The trend is to sintered
bronze sleeves, akin to an electric motor journal.
The same ceramic balls for your 2008 Record hubs fit most classic pedals
along the lines of an MKS Sylvan; more modern designs are seldom loose-ball
Dear Andrew,

Yikes! I googled and found ceramic cartridge bearings for pedals:
http://www.glorycycles.com/fsacecabefor.html

They cost only $139.90, a small price to pay for going . . .

Er, the PDF seems very confused about how much faster we'll be going.
http://lib.store.yahoo.net/lib/glorycycles/fsacer.pdf

First the PDF claims that using ceramic bearings can save "22m in just
55 seconds at 32kph. In short, astounding speed improvement of 4%."

In other words, you might go 33.28 kmh instead of 32.0 kmh, 4% faster.

But then the PDF claims that a "Record BB @ 100rpm and 400W consumes
0.6W, the same BB with ceramic bearings consumes 0.02W."

Let's round the ceramic drag down to zero and use this calculator:
http://bikecalculator.com/veloMetric.html

Tubulars, on-the-drops watts km/h
Record BB bearings 400.0 44.94
magic ceramic bearings 400.6 44.97 0.067% faster

Hmmm . . . a 0.067% speed increase is only about one-sixtieth of the
astounding 4% speed increase that we were promised.

To go 4% faster than 44.94 kmh speed with 400 watts, we need to go
46.74 kmh with . . .

This calculator tells us how many watts we need for 46.74 kmh:
http://bikecalculator.com/wattsMetric.html

We need 447 watts to go 4% faster than we went at 400 watts.

It's darned hard to get 47 extra watts by sprinkling ceramic bearings
in the transmission if the bottom bracket uses only 0.6 watts.

So I may wait a bit before I order those $140 ceramic cartridge pedal
bearings.

Cheers,

Carl Fogel

Ceramic bearings sometimes be found much less expensively than the
prices quoted in these postings. It takes a different talent than CF's
calculations of cost/watt to explain why there isn't price competition
for these. Could be in their failure rate?

I don't know why 3 fine shop owners here disparage them. While there
may be no way to honestly tout them (except for wear in some
applications?) why not let the fool and his money soon be parted if
the client wants them (unless warrantee replacement is too
frequent)?

But, I'd really rather know why I can't find replacement pulley wheels
for less than the price of entire cheap rear ders. Wait, that
dastardly Chris at Velo-Orange has 'em for $4/pair.

But, we've been here before. Suntour put ball bearing cartridges in
their excellent rear ders long ago, then smartly sold the pulley
wheels separately as an upgrade. Not that they claimed the wheels with
those bearing is why their ders shifted better. But, if the consumer
wanted to respect ball bearings more and believe that Campy bronze
bushings were primitive,

both campy and shimano use bushings for a reason - they accommodate
lateral play, something essential to quiet operation on modern
close-spaced sprockets.

well Maeda industries was happy to make many
extra bucks on the upgrades. As were shops.

Harry Travis