When it comes to ceramic bearings, we have to recognize what are ceramic bearings. There are two types of ceramic bearings in the market, one is full ceramic bearings, the other is mix ceramic bearings.
Full ceramic bearings are bearings whose balls and inner and outer rings are all made of ceramic materials, while mix ceramic bearings are something whose balls are ceramic but inner and outer rings are steel.
When using the same brand of bearings, ceramic bearings are indeed more expensive than steel bearings. The use of ceramic bearings also do increase the rolling efficiency of the wheel, thus achieving a more effort-saving effect. The power consumption of 0.8W can be saved by using ceramic bearings compared with ordinary bearings at 50km/h.
If the ordinary bearings are replaced by ceramic bearings directly under the same conditions, firstly due to the the difference of the gap in the bearings between ceramic bearings and steel bearings, the bearing installation position size of the hub is set in accordance with the original steel ball bearings’ tolerance and the pressure the bearings can bear. So if we modify and update to ceramic bearings on the basis of original steel bearings, It is easy to cause the short service life of ceramic bearings and the function of bearings can not play effectively.
Ceramics are twice as hard as steel, while they have only a quarter of the fracture toughness of steel. This means ceramics bearings are easier to break than steel bearings theoretically, meanwhile on the bumpy road while riding, the impact of ceramic balls on the inner and outer walls of bearings will cause concave and convex walls.
Therefore, under the two irresistible physical factors，it will test many hub manufacturers about the use of ceramic ball bearings. No one wants to bring himself more troubles.
However, we have our own opinions on ceramic ball bearings, and the ability to reduce rolling resistance is our driving force for the development of hubs. In fact, at least 90% of the problems can be avoided by improving the accuracy of hubs processing. Because there may be machining tolerance in every processing link. The closer the hub shaft and bearing are to the midpoint of a shaft, the lower the rolling resistance is, and the less pressure is exerted on the bearing.
Both Marvel and Drive use mix ceramic bearings in Elitewheels wheel set series. We put accuracy in the first place when processing the hubs. The tolerance of the bearing itself is also taken into account when determining the bearing installation position. Through higher concentricity of hubs, it can reduce the pressure of bearings so as to improve the service life of bearings and reduce rolling resistance, so that the function of ceramic bearings can be better played.
As a result of this experience, we have sold over 5,000 pairs of wheelset which uses ceramic bearings and they have been in use for over 3 years. Sales statistics and more users’ feedback have proved that our point is right.