CeramicSpeed in the dock

Hi I saw the post on ceramic bearings on road.cc and also this video (https://www.youtube.com/watch?v=vPWgtscgfa0) both of which seem to suggest ceramics bearings don't work as well as claimed? Anyone got any direct experience of this? Is it mainly hype? I see ceramicspeed have just launched a new product too with a lot of claims.
(http://www.bikeradar.com/road/news/arti ... eys-49782/)
thanks Maria
(http://www.bikeradar.com/road/news/arti ... eys-49782/)
thanks Maria
0
Posts
http://road.cc/content/forum/134304-cer ... d-bearings (data at link has changed)
Ceramics give a gain? yes
Ceramics give a big gain? No
Ceramics have downsides as well as upsides? yes
At the end of the day you pays your money and makes your choice, would I use them? No the cost is just too high for the somehwhat marginal gain, if I were running a pro cycle team would I use them? Yes probably, even 2 (or even about 10 if you do every bearing) is worth having then.
retired 9.6kg Carrera Kraken
The Carrera Hardtail combined thread - come on all you Carrera's!
The Sons Scott Genius RC20 build
Fixed TT 2015-2016
if you run ceramics with light oil you could save energy vs. grease, you could do that with steel too, bearing life would vary
but the video is just some stranger on the internet making claims based upon what he claims to be data from other sources, verifying the source data and context to determine if what he claims is actually relevant and true would take a lot of effort
it's youtube, he's got a channel, seems likely he's earning money from views and needs to generate clickbait
As for the power savings.... twice of censored all is censored all twice.
The rolling element material doesn't affect it much.
Graphs below:
What is more interesting is after a few 100km, the steel bearings are far more efficient.
Visit the Hambini Website
In summary, NTN Non-Contact are the way to go.
I am not sure. You have no chance.
Yes unless you need the sealing. Then censored are better - it's the OE fit on Hope stuff.
Visit the Hambini Website
The changes over time are very interesting though. Presumably this infers that ceramics are so hard that they can't really be "run in" like a metal-to-metal bearing interface?
Yes that's correct. Ceramic bearings are usually hybrid so they have metal races, the large difference in hardness causes the races to shred rather than bed. This is shown in the graph.
The technical term for it is Hertzian contact stress. This wikipedia article is quite heavy on the maths but there is an animation of a sphere being pushed into a yellow solid, a ceramic bearing behaves in this way
https://en.wikipedia.org/wiki/Contact_mechanics
Visit the Hambini Website
For what it's worth I run a cbear ceramic bottom bracket that is much, much better than the rotor one I had fitted before.
Adding grease to their bearings makes them spin just like any other (i.e. not fast).
Problem is, if you need grease in MTB jockey wheels, then you'll likely need it in road too, as UK winter roads hose the derailleur with gritty, salty, dirty water on a permanent basis. And if you don't then your £500 CS bearings are going to be toast in a matter of months. (or weeks)!
Same goes for BB, and as for headset, well if you're using ceramic bearings there, then you need your head examined!!
It is so unimportant that jockey wheels without bearings are just as fast
Following on from your comments on another thread about pointless purchases and rampant consumerism, ceramic jockey wheel bearings would seem to fall into that category. That people in some cases actually pay hundreds of pounds for this very dubious gimmickry is astounding. Of all the things on a bike you could throw money at to improve your speed this has to be the least productive on any cost/benefit analysis. It would be like expecting to improve your marathon distance personal best by paying someone 500 quid to cut your little toenail.
... or buying a more aero nipple lube
Visit the Hambini Website