Ceramic bearings: What's the point?

is there any point to them away from competition and competition conditions?
There are so many variations it's difficult to know what's hoodoo and what will bring holistic benefit.
The spiel mentions foreign object getting vaporized as ceramic is so tough. If this is true then they should be much better than the metal variants, no?
Full ceramics or semi (i.e. metal races)?
I know Fiddy swears by 'em but anyone here noticed any difference?

I'm considering for my rear hub by the way.

pm Dovvles

tiny bit less resistance and friction cos ceramic bearings are can be made rounder.
They are also harder which should make them more durable.
Using ceramic bearings in a non-cartridge bearing setup, that would mean the bearing race is softer than the ceramic bearings and as such the bearing race would deform before the bearings would = new hub time.
In hubs where chrome/stainless bearings are used, the bearings are the softer party and usually deform 1st and are replaceable = No new hub time.
this is why i would only use ceramic if they were cartridge.

I just worked out that logically not scientifically based on any research.. take with a pinch of salt.

From what I've read is that unless you are upgrading very top of the line hubs with already superior steel bearings then there are cheaper ways to make your hubs rock and roll better. Furthermore lots of people talk about the placebo effect, where difference is so microscopic on top end hubs it isn't worth the cost investment. But then at the same time, at the top of the game you are playing for tiny tiny improvements any way, so I guess the question some down to what you ride and how you ride it and how much cash you have spare to justify them. They certainly have lower rolling resistance.

Having had a pair of these in the shop I am certainly pondering the upgrade to Carbonayted bearings. http://www.philwood.com/products/bearings/carbonyte/ Fucking amazingly smooth. Maybe for the sunday bike ???

Planet X hubs ftw.

recently replaced a BB with a standard Hope one, my decent shop actively downsold me as I went in asking for ceramic, my rationale being that they were simply the best available.
They evidently need more regular greasing, and for all but out- and -out race bikes probably not worth the investment. Not not sure whether that helps but its another experience shared.

good to know

The place where people comment on the ceramic making a noticeable difference (on the work stand, the actual power saving is all but undetectable on the road, and way smaller than the measurement resolution of your legs) is in the Campag Super Record BB, but that is all down to the fact that they do without rubber contact seals due to the above mentioned contamination-squishing properties of the bearings. You can get the same benefit on a bike with steel bearings by using shielded, rather than sealed, cartridges. The penalty is shorter bearing life, especially in wet or dirty conditions.

If I were going to use ceramic anywhere, it would be in the derailleur pulleys, because most stock pulleys use bushings rather than roller bearings, so you're upgrading an already high friction bearing to one which has very low friction and should stay that way in the horrible conditions to which they are subjected. Since the loads on these bearings are quite small, and they are not subjected to the shock loads which trouble every other bearing on a bike, you can use full-ceramic cartridges too.

Ceramic bearings: What's the point?

There is a simple answer, which does not need the 8 or so posts above and that is: There is no point.

I got full ceramic bearings for the Mack hubs as the ones in my Zipp's just amaze me everytime I ride them. If you're looking for a tangible benefit then flip the bike over and spin one of the wheels, come back 2 minutes later and it'll still be spinning. This must have some kind of benefit on the road/track?

Worth the cost?

NO

so the bearings are made of clay right?

Yup, made by small-handed Chinese orphans...

If you're looking for a tangible benefit then flip the bike over and spin one of the wheels, come back 2 minutes later and it'll still be spinning. This must have some kind of benefit on the road/track?

Maybe, but then maybe it won't be measurable or significant once the resistance factors of the chain drive, tyres on surface friction and aerodynamics are in effect?

I nearly agree.

For me their is no benefit on a fixed wheel bike that I can feel, on a road bike they definitely make a difference when descending.

have you tried using plastic bb gun pellets? Work a treat

For me their is no benefit on a fixed wheel bike that I can feel, on a road bike they definitely make a difference when descending.

To get more benefit for less, have somebody hand you a full water bottle as you go over the top. At 30mph down a 1:12 slope, 500ml of water will add just over 5W to the power which is overcoming the aero and rolling resistance. Total wheel bearing losses, even including seal drag which is not changed by swapping to ceramics, are less than that.

Did you do controlled blind trials comparing steel bearings with ceramics? I say it's all placebo if you claim to feel a difference, or even measure one with an on bike power meter, as the improvement is below the measuring resolution of Powertaps and SRMs

The place where people comment on the ceramic making a noticeable difference (on the work stand, the actual power saving is all but undetectable on the road, and way smaller than the measurement resolution of your legs) is in the Campag Super Record BB, but that is all down to the fact that they do without rubber contact seals due to the above mentioned contamination-squishing properties of the bearings. You can get the same benefit on a bike with steel bearings by using shielded, rather than sealed, cartridges. The penalty is shorter bearing life, especially in wet or dirty conditions.

I don't think the hub was made with UK weather conditions in mind, the bearings seem fairy exposed, so I'll probably blank the shielded option. Given this is there's an argument that full ceramic at a reasonable cost might be better in the long term. How much longer are they meant to last over their steel counterpart? (cos if its 3x as long then 3x the price + better performance makes sense)

What did you pay, Dov?

He paid way too much!

Lots and lots! Ha ha.

From my research the precision rating of the bearings probably has more effect than ceramic or not, although ceramic should definitely last longer (which would be my priority if they didn't cost so much).

From what I gathered anything 5 or above on the [ame="http://en.wikipedia.org/wiki/ABEC_scale"]ABEC scale[/ame] is more than good enough for bike use.

I have ceramic bearing BB's in the fixie skidder, and the SS 29er.
Do they offer any benefit?

not as much as bloody gears would ;)

To get more benefit for less, have somebody hand you a full water bottle as you go over the top. At 30mph down a 1:12 slope, 500ml of water will add just over 5W to the power which is overcoming the aero and rolling resistance. Total wheel bearing losses, even including seal drag which is not changed by swapping to ceramics, are less than that.

Did you do controlled blind trials comparing steel bearings with ceramics? I say it's all placebo if you claim to feel a difference, or even measure one with an on bike power meter, as the improvement is below the measuring resolution of Powertaps and SRMs

+1
You just can't get away from F=ma

I agree with Dov (rare) in that on long downhills I feel the difference on my road bike simply that I roll farther and faster without pedalling. But that's it... that's the only time I claim to feel a difference.

There aren't enough mountain descents in West London to justify the cost of ceramics, but I still put them on my road bike as I am lured to the reduced maintenance. This only works if you have ceramic on ceramic... steel races for ceramic bearings potentially reduces time between changes (impacts such as potholes can smash the bearings... and don't even think about it for off-road use).

So they can be worth it if you're maintenance averse or lazy on that front... and they can be worth it if you have a road bike and many mountains to shoot down... but just for cycling around London? No, they're as useful as some shaved legs.

^^listen fes, save the money. u order skf cartridges and enjoy a smooth ride as can to, now that you have a bit more cash spare, many more beers.

I was only able to buy the cheapo non-stainless steel versions (black, not red seals) from Condor. They will die in no time. Decent stainless ones are around the tenner mark, and they haven't fared too well in the past, as I said I feel the hubs were designed with California weather in mind. I don't want to be changing every three-four months.
Now I'm 90% sure I saw a full ceramic for around $70 (approx £40). If ceramics are harder wearing, lower resistance, zero corrosion, and vaporize foreign objects entering (bit like Nick Griffin, really) then surely this makes sense.

I've not noticed bearing wear on any other hub as much with these hubs. if the bearings were hidden then, yup, I'd go for what my wallet would like. I'll see how these cheapos do before a decision.