Had an argument over ceramic bearings.

[novetan]

Recently I had an argument with a friend who insist that using ceramic bearing in the hub will go faster. I beg to differ from him and gave him the reason that the perceived more free spinning wheel will be retarded by the frictional force between tyre and road. I cited him an eg. if the coefficient of friction between road and tyre is 0.5 and coef. of friction between ceramic bearings and hub is 0.2, then the wheel can never overcome the gripping forces between tyre and road, which means pure waste of money, unless we are riding on ice in which the wheel may not even spin but skid or slides. BTW, I do not know what's the COF between road and tyre, just pure guess but think it will never be lowered than COF of bearings.

Is my argument correct?

And btw, if you think ceramic bearing will speed up our riding, all things being equal, pse tell me what’s the reason behind it?

 

[G2EWS]

Logic seems to imply that the two drags will be added together?

But logic is not always right and I don't have my engineering hat on at the moment.

Regards

Chris

 

[gavintc]

Adjust your brakes so that they bind a little, go out for a cycle, and then reconsider your comment.

 

[raindog]

Or tighten the cones very slightly on your wheel bearings, then go for a ride.

 

[Pedrosanchezo]

I think we are talking marginal gains here but if combined with other marginal gains then the gain will be greater.
Slight weight saving and less resistance means less effort.

http://www.dailypeloton.com/displayarticle.asp?pk=19501

This link has a little on the subject and why they do what they claim.

 

[Mr Haematocrit]

As someone who has ceramicspeed bearings in all his bikes frame BB, wheels etc and just brought a new frame with them as standard, I can only state my real world experience of them.
Do I believe they make you any faster, probably not unless descending and then you become aware of how good they are, the vast majority of people start pedalling before you even need to.
I also find that bikes fitted with ceramic bearing climb hills a little easier and that I suffer from fatigue less during long runs on bikes with ceramic bearings, is this due to reduced effort, or perceived reduced effort.. I do not know, the reality is placebo can be a powerful thing.

I can tell you for certain that if you suspend the bike and spin a wheel fitted with a ceramic bearing it spins for a longer period than a wheel with a standard bearing. What this amounts to in real terms Im not sure.

This is the BB of my new frame and if the ceramic bearing does not help things, I bet the sticker alone makes the bike faster

 

[400bhp]

Emperor's new clothes.

Tell the difference

 

[black'n'yellow]

Ironically, the stickers will probably give you more 'real world advantage' than the bearings themselves...

 

[400bhp]

I've got a carbon water bottle.

It makes me go faster.

 

[Mr Haematocrit]

Ironically, the stickers will probably give you more 'real world advantage' than the bearings themselves...

You have no idea how fast I am these days, not only does my bike have ceramic bearing stickers, it has a decal on the frame which says carbon which clarify it as being an exotic material... When you put all this into consideration and then realize I run zipp wheels you know that I'm getting performance..... I mean zipp even sounds really fast, even without the stickers they plaster all over the wheels.... I know your Cat3 but personally I think the tour is within reach for me. I even have a Yellow Jersey, it's a livewrong one as apparently these were the fastest for seven years before the owners had to give them all back. Also growing sideburns as we speak
It's all marginal gains, but whooosh is what Im thinking.

Only thing for certain is I can't prove or dispute anything, but the fact remains you can have any kit you want, but if the engine is shite, its going nowhere fast.. I have had my arse kicked in Cat4 by people on seriously old bikes, I buy what I like because I can, but imho people need to realise nothing is a replacement for structured training and hard work.

 

[oldroadman]

If a bearing runs easier, then why not use it? Ceramics are used a lot in other applications, and are seen to be successful. Given that the bike is correctly prepared, if the ceramics run even 1% easier, then you go a tiny bit faster for the same wattage output. What's not to like?
All these "marginal gains", as used by GBCT, plus of course talented and brilliantly prepared riders, have got the elite end of the sport to the position it's in today.
Looking back at history, underfunded (cont'd P.94.........)

 

[Drago]

I ran may old Lappiere on a full ceramic bearing BB and it felt weird, uncannily free, almost as if I was pulling too low a gear. There's no doubt that eliminating frictional losses will make you go faster for the same amount of energy, but I don't think the gains are substantial. More trimming at the edges, half a percent here, half a percent there sort of thing.

 

[oldroadman]

I ran may old Lappiere on a full ceramic bearing BB and it felt weird, uncannily free, almost as if I was pulling too low a gear. There's no doubt that eliminating frictional losses will make you go faster for the same amount of energy, but I don't think the gains are substantial. More trimming at the edges, half a percent here, half a percent there sort of thing.

Exactly - and those little things add up.

 

[Cyclopathic]

I've got a carbon water bottle.

It makes me go faster.

I use water that has only one hydrogen atom making it lighter than normal water.

 

[Cyclopathic]

Plus which you can make a saving by making your own ceramic bearings. Just roll up some clay into tiny little balls, aply a glaze (salt can be used for this) and pop them in the oven on a high gas mark for about 40 minutes.
I've not tried this yet but it's bound to work. Isn't it?