The folks at enduro bearings argue that for bicycles the materials are far more important than abec ratings and that for most applications abec 3 and 5 are appropriate for all things bicycle.
Ceramic bearings vs steel bearings bicycle wheels.
Rolling resistance is the key trump card promoted by ceramic bearing fans.
The other apparent advantage of ceramic is that it is a harder material.
So for safety reasons ceramic wheel bearings on bicycles are in fact almost always hybrid design meaning ceramic balls on steel races.
How to get the best performance from ceramic bearings ceramic speed.
Cracking a race could stop a wheel from turning instantly and no good comes of wheels permanently locking up on a bicycle.
It takes weeks for a kogel ball to sit in a tumbler and be perfectly polished.
The ceramic balls are often silicon nitride or equivalent.
This is due to the hardness of the bearings.
Second well made high quality ceramic bearings can have a significantly longer lifespan than the commonly used stock steel bearings that come installed on most production bikes.
This is mostly due to the additional time spent to perfect a quality ceramic ball.
Because ceramic races are more brittle than steel.
Ceramic bearings are in actual fact hybrid.
They are also lighter than equivalent steel bearings so swapping to ceramic bearings will reduce the weight of your bike.
They use ceramic balls and usually a steel inner and outer race.
While regular bearings are made from stainless steel ceramic bearings are made from ceramic silicon nitride si2n4.
The material can be polished smoother than any metal reducing friction and wear.