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HI All,
Sorry if this has come up but is a Ceramic Bearing BB such as the one FSA is offering of any value (performance wise)? Any experience and or insight would be appreciated. No point in spending the cash on a "percieved" or "neglible" gain.

I hear ceramic bearings last longer but I'm more concerned with performance gains such as less friction therefore less energy expended while pedaling.

FSA in particular claims "up to" a 4% reduction in effort, particularly at slower speeds (should I assume lower rpm?).

As relates to wheel hub bearings I guess one would assume lower rolling resistence and better preformance too.

So is all the above marketing hype or a true value when looking for a performance gain?

Thanks
 

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The particular ceramics used for bearings is considerably lighter than the steel used (50110 if they're good). Additionally they are much harder and therefore do not deflect as much when loaded, this yields a smaller contact area thereby reducing friction.

As for a noticeable improvement, probably not, but they should last longer, ceramics (if properly designed) have excellent life.
 

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uhhhh, what?
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basically hype...

ceramic bearings shine in high rpm applications; 10k, 30k, 50k kinda stuff. what's your average cadence, 100 or so, 150-180 if you're really winding it up? given the price premium over quality steel bearings there's absolutely no reason to convert to ceramic unless you have absolutely nothing else left to drop your hard earned cheddar on.
 

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Wouldn't help me noticeably, but...

I'm positive I wouldn't feel the difference--a few grams in weight and a 4 percent reduction in friction over a system that already works well would be lost amid the thicket of my inconsistencies, inefficiencies and tendency to say, "The hell with THIS, I'm going to coast awhile."
I read a story one time, though, about the THEORETICAL benefits of stuff like this--they measured the performance of some standard components against that of supposedly upgraded versions, then projected them out to a theoretical time trial. None of the test riders could feel the difference when they rode, but in the computer, they translated to reductions of as much as 25 seconds in a TT (I think that was aftermarket rear derailleur pulleys; can't remember for sure). So it may not be money down the plumbing...but it's a lot of money for a pretty small gain, I imagine.
 

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Cannot bench own weight
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I know they make ceramic bearing replacements for Zipp and Mavic wheels. I was wondering the same thing. They want something like $350 to upgrade the bearings. No Thanks!
 

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You could always just get a hub that uses loose ball bearings and replace the bearings with ceramic ball bearings, it'd be cheaper, and you could spec certain properties if you wanted.
 

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I've read ceramic wheel bearings can save about 1 watt per wheel. I would imagine cranks would be something less than that, since they turn slower than the wheels.

The reason FSA claims "especially at lower speeds" is that, unlike wind resistance, the percentage of effort used to overcome mechanical friction like bearings goes down as speed goes up. You would notice the lower friction of a ceramic wheel bearing much more if you spun it on a stand, for instance, than if you were riding.

I think they are probably worth something, but far, far, far, far less than they charge for 'em.
 

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Keep in mind that the pros use oil in their BBs and wheel hubs to reduce friction. Changing from grease to oil would make a much larger difference than going to ceramic bearings. The downside with oil is that you have to top it up every day.
It all breaks down to how competitive and serious are you about racing? If you've trained pro-level hard and done everything you can to make you and your bike fast already, then you want to cap it off with oil-lubed ceramic bearings.
Me? I'm too old, slow and non-competitive to bother. Already spent an obscene amount on my new bike and have to ride more to enjoy it more.
 

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Call me a Fred
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Steel ball bearings have low resistance. A 4% reduction of an already low number is meaningless given the large wind resistance that cyclists contend with.
 

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I am an aircraft mechanic. Aircraft engine drive shafts endure incredible stresses and require an incredible amount of uninterrupted cooling and the least amount of friction as possible. Each shaft uses mainline bearings. Each set has an inner and outer race. What are the bearings in aircraft engines composed of? Hardened steel. What cools the bearings? Highly pressurized engine oil.

Now how come multi-million dollar aircraft engines do not instead use ceramic bearings? Probably because of cost. And more likely the cost to weight/friction/energy savings ratio proves inconsequential to airlines trying to save every penny on fuel. Aircraft engine quality ball bearings are machined by a computer controlled lathe. And they have been a proven product for decades.

$ave your money for better gear/better bike, blow it in the stock market or keep it in the bank. Unless you are a sponsored athlete needing to shave a second every 4th or 5th mile or unless you like to see your money ease out of your wallets like they were on steel bearings, do not spend your money on these ceramic bearings!
 
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