Ceramic Bearings

stevie_b

anyone using ceramic bearings? for hubs, bottom bracket, pulley wheels etc.

while i would gladly take the extra watt they reportedly give you, are they worth it? do they need any more maintenance than standard bearings?

Lumen

The SRAM Red ceramic bottom bracket claims to need re-lubing every dry 100km. The inconsequential power savings come from using thinner grease.

Life is too short.

Murph100

Have some on my Campag SR, yeah sure its nice and the cranks fly around forever when on the workstand with the chain is off, but unfortunately I haven't figured out how to actually ride the bike with the chain off

By the time you factor in the various sources of drag, however small, like the chain, interface between chainring, sprockets & pulley wheels, rear hub, grease, tyre RR and road surface etc, the watt savings with ceramic bearings IMHO are a load of boll!x, but absolutely essential if you like spinning things on a workstand

stevie_b

yeah it doesn't look like they're worth it from a cost : performance point of view. it seems that to get any benefit you need to be running unsealed ceramics with very light oil - but this in turn would require a lot of maintenance. running ceramics with your normal grease would seem pretty pointless.
or maybe someone who uses them can argue otherwise?

Murph100

Mine are running with just the Campag Oil they came with and actually require very little maintenance, so yeah they are really smooth etc but any benefit they may have, is completely lost when you consider the drivetrain as a whole.

Get the whole bike fitted with ceramic bearings if you want, I promise you the only 'real world' difference you'll feel will be in your wallet, but you can make You Tube videos on your workstand ... if that floats yer boat

In the end its just a load of balls

Single Malt

If the few watts saved are the difference between winning and losing, then ceramic bearings become useful

Murph100

You're talking less than a watt, and thats according to the manufacturers, and doesn't take the rest of the drivetrain into consideration so in reality way less than a watt.

Single Malt wrote: »

If the few watts saved are the difference between winning and losing, then ceramic bearings become useful

AstraMonti

Back from the dead.

Has anyone seen any research or comparison between steel and ceramic bearings in bicycle parts? It's impressive how many people believe that they gain something (something more than 1 watt that is) by using them but I haven't actually seen anything that proves that statement (or disproves it). There is a whole market around them now and I am just interested to see if there are any real world data out there.

Lumen

AstraMonti wrote: »

Has anyone seen any research or comparison between steel and ceramic bearings in bicycle parts? It's impressive how many people believe that they gain something (something more than 1 watt that is) by using them but I haven't actually seen anything that proves that statement (or disproves it). There is a whole market around them now and I am just interested to see if there are any real world data out there.

You've completely lost your mind.

AstraMonti

hahaha I guess that's a no.

kumate_champ07

Waste of money, some wheel manufactures have admited it and just use highest grade steel bearings. Every industry needs a gimmick, plenty out there with fat pockets wanting that little bit extra performance. The reason you wont find research on ceramic bearings in actual use in bicycle parts is that the results would show theres no improvement and then nobody would buy them

Lumen

AstraMonti wrote: »

hahaha I guess that's a no.

A more serious answer can be found here:

http://forums.roadbikereview.com/wheels-tires/ceramic-bearings-not-217316.html
http://forums.roadbikereview.com/components-wrenching/ceramic-speed-vs-enduro-ceramic-bearings-94754-2.html

"I recently tested some derailleur pulleys with plain (sleeve) bearings vs some stainless steel ball bearings and found that under typical conditions the steel ball bearngs in your derailleur consume about 60 mW at full speed - that figure is for two bearings with a load (as applied by the cage spring). The advantage of ceramic over steel is thus limited to less than 60 mW, and remember these are the bearings where the power consumption is likely to be the greatest. "

levitronix

you ll never spin a bike wheel fast enough to get the real benifit of ceramic bearings, they re more suited where heat build up and particle migration is a factor or static build up has to be avoided because they re non conductive

Youd save more in drive looses if you changed the type of lube you use, but then youd have to change it daily

But if you think you need them get them , talk to a bearing expert and they laugh about road bike applications

AstraMonti

I kinda know that, but it amazes me how easily people suggest (thankfully not in this forum) that if you go to ceramic your life will be so much better and you might even score more ladies*. There are so much more that you can change for 100euro on your bike that would make a difference than the bearings.

*Might exaggerate a bit just to get my point across

levitronix

Lumen did mention dearailuer pulleys, they take a beaten ! id guess a ceramic nitride being harder than steal might last a bit longer , i ve ground down the plain bearings on a 105 dearaileur on my winter beater, but saying that those jockey wheels didnt even have propper bearings

Chips Lovell

I'm not sold on ceramic bearings for reduced friction. Having said that, I like the idea of corrosion proof bearings, having already replaced two different sets of bearings for that reason (primarily down to my own laziness in not servicing said bearings sooner).

levitronix

for a wheel hub a grade 3 bearing is more than enough

doozerie

AstraMonti wrote: »

Has anyone seen any research or comparison between steel and ceramic bearings in bicycle parts? It's impressive how many people believe that they gain something (something more than 1 watt that is) by using them but I haven't actually seen anything that proves that statement (or disproves it). There is a whole market around them now and I am just interested to see if there are any real world data out there.

Any of the (few) studies/research that I've seen mentioned have been within discussions of ceramic bearings in a cycling context. The studies though were carried out on the bearings being used in an industrial (or possibly aeronautical, can't recall for certain) context. I seem to recall that the same study was being hailed by supporters of ceramic bearings as evidence that they are beneficial for cycling, and by non-supporters as evidence that they are not. In those same discussions even those in the former camp though seemed unable to put together a convincing argument that they were a good choice when you factored in the high cost of them.

The prices I've seen listed for ceramic bearings I find ridiculous, yet I've seen magazine articles (Cycling Plus) casually refer to them as if their benefits were well known and significant, making them worth the price. Either the writers have access to information that the general public don't or they've simply bought into the hype (the latter, I suspect). I saw some mention recently of ceramic bearings coated in titanium, so maybe the industry are now trying to drum up yet more hype.

levitronix

the silicon nitride is harder than ti

levitronix

The simple fact is sell a premium product you need to sell it with premium materials this helps sell the product and exaggerate the hype

doozerie

levitronix wrote: »

the silicon nitride is harder than ti

I now feel an irrational desire for a silicon nitride frameset, with concrete forks (for "give"). Curse my gullibility!

dave2pvd

I seem to remember an old article/interview with Zipp with the main theme being something like "why don't we spec ceramic bearings". The reason they used was simple enough: there's no benefit. Furthermore, they lamented the fact that people were fitting aftermarket bearings to their hubs that had a lower Grade/ABEC rating.

The point being, 'ceramic' means nothing in terms of rolling resistance for cycling applications. Specs on the ball bearing unit itself (ball grade, ABEC rating) are what counts in an unsealed/unshielded bearing. BUT: in cycling, neither of those matter much as far as resistance goes, assuming you are buying high spec bearings in the first place. Resistance tends to be a function of seal drag, and not much else.

Was it Cycling Weekly that was THE cycling magazine in the 80's? I think so. The UK was TT mad back then. Competitors were seeking every advantage to eke out a few extra seconds. One of the techniques described in the magazine was to remove the bearing seals! I'll bet Graeme Obree never bothered with that.

FYI: Zipp now sell ceramic bearings.

Chips Lovell

Obree got his bearings out of his washing machine.

dave2pvd

To address an earlier point re Shimano derailleur pulleys: replace them early. Basic Tacx pulleys are the way to go. Far superior bearing units than Shimano's sleeved/bushed pulleys. With real seals, not shields.

Keep_Her_Lit

Lumen wrote: »

The SRAM Red ceramic bottom bracket claims to need re-lubing every dry 100km. The inconsequential power savings come from using thinner grease.

Only if your average speed is 1km/h (linky).

But it gets even more ridiculous: "Re-grease bearings immediately following any significant exposure to water (heavy rain; water crossings)."

Sorry chaps, I just cycled through a puddle - have to pull up here for a mandatory re-grease. See you on next week's training spin, weather permitting.

Life is too short.

Agreed.

Holyboy

All the above aside (and this is only my understanding of it) steel balls will wear, pit etc, which will leave them running rough and in obvious need of replacement but if a ceramic ball fails it shatters completely, would any one like to take the chance?

gman2k

I've a Wheels manufacturing ceramic bearing BB on my hardtail, and it spins the cranks beautifully - way smoother than the XT BB I had on first. (When the bike is on a stand).
It doesn't make any difference out on the trail though.

Lumen

Keep_Her_Lit wrote: »

Only if your average speed is 1km/h (linky).

Aha! I misremembered the documentation.

studiorat

Vladimir Kurtains wrote: »

Obree got his bearings out of his washing machine.

he used the same ones, not the actual ones I believe.

otherwise his Ma woulda killed him...

doozerie

studiorat wrote: »

he used the same ones, not the actual ones I believe.

It has been a while since I read his book but I think he did actually take them from a washing machine for this first version of the bike. As far as I can recall he chose them because they were ideally suited to the narrow bottom bracket that he had designed. For subsequent versions of this bike I think he had a comparable set fabricated.

The bearings in a washing machine must actually be quite good quality. Our washing machine is still spinning well after over 10 years of regular use. Stick a tyre over the drum and it would probably go like the clappers, outperforming anyone on ceramic bearings. Might need a particularly long extension lead though, and no doubt the UCI would kick up a fuss.

dave2pvd

gman2k wrote: »

I've a Wheels manufacturing ceramic bearing BB on my hardtail, and it spins the cranks beautifully - way smoother than the XT BB I had on first. (When the bike is on a stand).
It doesn't make any difference out on the trail though.

The seals must be useless

Don't forget to re-lube after every puddle.