Steel or ceramic

cyco2

I have only just found a supplier of ceramic balls and I was thinking of changing them for my steel ones. Do you think I would notice a change in performance? How could I measure the difference? Do I still need to use grease or are they used dry?
At my age I need all the advantages I can get because I am fed up of getting scalped and I was hoping a change in ball material would give me a bit of a boost. Has anybody else used them with benefit? Or should I just keep riding with the wind?

Wooliferkins

I'm sure your Missus would be appreciative of the change of balls. All bearings need lubing. Do you need minimal gains mechanically or lose a K or two and get fitter?

rolf_f

cyco2 wrote:

I have only just found a supplier of ceramic balls and I was thinking of changing them for my steel ones.

I don't know - what does your wife think? She might find ceramic a bit less cold.........

Pokerface

Unless you are competing at an Elite level, you don't ceramic bearings. You won't notice the difference - except in your wallet.

desweller

Ceramic bearings have absolutely no application in bicycles. The temperatures and speeds are far too low for the advantages of ceramics over engineering steels to be realised. It's purely a marketing exercise.

cyco2

Wooliferkins wrote:

I'm sure your Missus would be appreciative of the change of balls. All bearings need lubing. Do you need minimal gains mechanically or lose a K or two and get fitter?[/quote

My Missus would be seriously upset. Probably accuse me of having a girlfriend. Anyway, the point about losing a few k is a must and I would gain far greater benefit than ceramic balls. Thanks.

P.S. Do ceramic balls need a special lubricant ?

Pokerface

Pokerface wrote:

Unless you are competing at an Elite level, you don't ceramic bearings. You won't notice the difference - except in your wallet.

Interesting follow up to my previous comment. I recently had the opportunity to upgrade several of the bearings on my bike to ceramic and the difference (to me) was actually noticeable. Possibly placebo effect - but there is no doubt that they spin better.

Wrote about it here for anyone interested: http://637daystogo.blogspot.com/2011/08 ... rings.html

desweller

PF - you should be aware that the best way to get free-spinning bearings under low load conditions (e.g. spinning the crankset with your hand) is to run them dry or with a very light oil and without seals. Obviously this is not representative of how the bearing should be run under loaded conditions in a hostile environment, so an unloaded coastdown is not a good test of bearing efficiency.

Your ceramic bearings might also be a different design - e.g. point contact rather than deep groove.

Note that the maximum speeds typically encountered by bicycle bearings do not approach their rated limits so the max centripetal load of the bearing is not a factor.

EDIT: Should have read shallow groove vs deep groove

Pokerface

DesWeller wrote:

PF - you should be aware that the best way to get free-spinning bearings under low load conditions (e.g. spinning the crankset with your hand) is to run them dry or with a very light oil and without seals. Obviously this is not representative of how the bearing should be run under loaded conditions in a hostile environment, so an unloaded coastdown is not a good test of bearing efficiency.

Your ceramic bearings might also be a different design - e.g. point contact rather than deep groove.

Note that the maximum speeds typically encountered by bicycle bearings do not approach their rated limits so the max centripetal load of the bearing is not a factor.

It's entirely possible that a good set of steel bearings would give the exact same performance as the ceramic ones. I don't know enough to judge. But the ceramics are lighter and (at least in this case) spin better than the steel ones I had previously. Talking about 2 new BB's - one steel and one ceramic. The ceramic one performs much better.

(And as I said in my review - having lost a World Cup TT by 0.4 of a second, I'm not taking any chances. If new bearings get me that time back and I win the next one by as slim a margin - it was worth it!)

kayakerchris

Just swapped to ceramic bearings from standard bottom bracket. I also swapped ultegra to full Di2 so not completely equal test but a significant change in feel.

I have also swapped SRAM Rival external BB bearing to ceramic and Ultegra on commuter bike and again notice a big difference in smoothness.

Would losing a few kg make more difference to the distance I can cycle. Yes.
has the upgrade been worth it. Definately

desweller

PF - if you're not concerned with bearing life on the race machine then you might get a minor improvement by removing the seals from the bearings and replacing the grease in them with something less viscous (especially as you must be pretty light compared to the limits that the bearings would have been designed for).

neeb

DesWeller wrote:

PF - if you're not concerned with bearing life on the race machine then you might get a minor improvement by removing the seals from the bearings and replacing the grease in them with something less viscous (especially as you must be pretty light compared to the limits that the bearings would have been designed for).

Isn't this exactly the advantage of ceramic bearings though, the fact that they CAN be run with minimal lubrication without wearing out nearly as quickly as steel bearings under the same conditions?

Monty Dog

Ceramic bearings are popular with the inline speed skate fraternity - you run 16 at a time but to get any real benefit you run them without seals and use oil not grease. However, it means you have to clean them every time which would be a right faff with a bike.
The evidence that they are of any benefit for bikes is somewhat dubious, usually from people who've paid £300 for the privilege - a new, clean chain has more benefit.
Finally, the prices charged for 'bike' specific ones is a rip-off - you're often paying 10x premium over standard ceramic bearings.

gavbarron

http://www.bikeradar.com/gear/category/ ... -11-45042/

Pokerface

DesWeller wrote:

PF - if you're not concerned with bearing life on the race machine then you might get a minor improvement by removing the seals from the bearings and replacing the grease in them with something less viscous (especially as you must be pretty light compared to the limits that the bearings would have been designed for).

I'm using bearings designed to be used with little lubrication (dry lube) and they have special non-contact seals. Sounds like they have already integrated the performance enhancements you are talking about into their design!

(As an aside, Wiggins uses bearings from the same company - and runs his front wheel with no seals or dust shields, etc).

http://ultimateceramicbearings.co.uk

ride_whenever

TBH, i've got a few bikes with ceramic bearings in.

For me it's about maintenance though, they're much more durable.

P_Tucker

DesWeller wrote:

Ceramic bearings have absolutely no application in bicycles. The temperatures and speeds are far too low for the advantages of ceramics over engineering steels to be realised. It's purely a marketing exercise.

Actually, this is incorrect. Ceramic bearings lighten your wallet enough to take a few seconds off your time up the Tourmalet.

Obv the bearings themselves do the square root of f**k all.

StageWinner

I'm sceptical on the claimed benefits (I'm guessing mostly by manufacturers) of ceramic bearings.

To all those that say they don't do anything - is there any 'proof' of this out there? DO they even last longer or is this a false claim too?

If they offer no benefit whatsoever, can manufacturers get away with saying they do?

oldwelshman

I have heard claims from some one who sells these that they reduce power requiered by 7 watts comparing to steel BB's which I think is a bit extreme, not seen any data though.
The usual comment is how easy the cranks turn with no chain, but the steel BB's do the same and the effort to turn cranks with no chain is almost nothing.
Put a chain on and see how more you need to turn cranks as someone above stated more beneficial to have a good and well aligned chain.
I have tried ceramic and felt no difference at alll and saw no improvement in performance.
I stand to be corrected though and if data was shown to improve performance by 7W I would buy them

Butterd2

I too swapped out my standard BB for a ceramic one (£30 from eBay). The crank certainly spins more freely and it did feel noticeably smoother (poss placebo). Did it improve my performance though, of course not (certainly not measurably).

gilesjuk

Pokerface wrote:

(As an aside, Wiggins uses bearings from the same company - and runs his front wheel with no seals or dust shields, etc).

http://ultimateceramicbearings.co.uk

That's because he can change his bike or wheels before every single race.

A formula 1 car is faster than my diesel estate, but I know which will last longer.

desweller

neeb wrote:

DesWeller wrote:

PF - if you're not concerned with bearing life on the race machine then you might get a minor improvement by removing the seals from the bearings and replacing the grease in them with something less viscous (especially as you must be pretty light compared to the limits that the bearings would have been designed for).

Isn't this exactly the advantage of ceramic bearings though, the fact that they CAN be run with minimal lubrication without wearing out nearly as quickly as steel bearings under the same conditions?

That's a reasonable statement. I'd like to see some coastdown figures in controlled laboratory conditions with a range of loads and lubricants before claiming anything. I'd be extremely surprised if the efficiency gains are more than 1% (which might be worth it for someone like PF).

P_Tucker

The other thing worth remembering is that comparisons are generally done between sh!t steel ball bearings and good quality ceramics. You can buy good quality steel ball bearings for a fraction of the cost of ceramics, but for some reason possibly related to £££, you don't seem to be able to easily buy good quality stteel ball bearings from a bike shop.

And if you must get ceramics, for the love of Raptor Jesus don't get them from a bike shop. They're at least twice as expensive as exactly the same thing from a hundred bearing shops you can find using google.

P_Tucker

DesWeller wrote:

neeb wrote:

DesWeller wrote:

PF - if you're not concerned with bearing life on the race machine then you might get a minor improvement by removing the seals from the bearings and replacing the grease in them with something less viscous (especially as you must be pretty light compared to the limits that the bearings would have been designed for).

Isn't this exactly the advantage of ceramic bearings though, the fact that they CAN be run with minimal lubrication without wearing out nearly as quickly as steel bearings under the same conditions?

That's a reasonable statement. I'd like to see some coastdown figures in controlled laboratory conditions with a range of loads and lubricants before claiming anything. I'd be extremely surprised if the efficiency gains are more than 1% (which might be worth it for someone like PF).

Depends what the races are made of, innit? If they're steel, the ceramic bearings will just wear them away as steel bearings do. I was always led to believe that ceramic races weren't suitable for bike applications, being too brittle, but I think they've started selling them in bike shops (for £££). Interested to see if anyone who knows about this sort of stuff can set everyone straight

Pokerface

DesWeller wrote:

neeb wrote:

DesWeller wrote:

PF - if you're not concerned with bearing life on the race machine then you might get a minor improvement by removing the seals from the bearings and replacing the grease in them with something less viscous (especially as you must be pretty light compared to the limits that the bearings would have been designed for).

Isn't this exactly the advantage of ceramic bearings though, the fact that they CAN be run with minimal lubrication without wearing out nearly as quickly as steel bearings under the same conditions?

That's a reasonable statement. I'd like to see some coastdown figures in controlled laboratory conditions with a range of loads and lubricants before claiming anything. I'd be extremely surprised if the efficiency gains are more than 1% (which might be worth it for someone like PF).

1%!! I would be happy with a 1% performance gain! Hell - I'd be happy with a 1 second performance gain over standard steel bearings (over a 10 mile TT).

(I didn't pay for the ceramics before anyone calls me a fool for paying exorbitant amounts of money for a 1 second gain. I also found 'standard' ceramics online for basically the same price as steel.)