Ceramic Bearings: What are they?
It is important to remember that the ceramic bearings used in racing are constructed using conventional hardened steel races, but with ceramic balls replacing the common steel type. Without question, ceramic bearings raise the performance bar a significant amount.

The two most significant reasons for this is they are 58% lighter in weight than steel balls and due to the way they are made, they are “rounder” than steel types. How much “rounder”? Modern steel bearings typically will have tolerance variations between 50 and 60 millionths of an inch, whereas a grade 5 Cerbec ball will only have 10 millionths variation, a considerable difference. Again, due to the way they are manufactured, ceramic balls have are an improved surface finish compared to steel balls.

Both of these factors are the reason for the improved smoothness that is apparent the moment you spin one vs. the other. Just think of the combined effect of lighter weight and reduced vibration when it comes to crank bearings!

Why are ceramic bearings better?
There are other advantages that should be taken into account. The ceramic balls in ceramic bearings have a considerably lower amount of thermal expansion compared to steel types. This allows tighter tolerances, if needed. They also run cooler in operation. This reduces ball expansion and improves lubricant life.

The balls in ceramic bearings are much harder than steel balls (over 100% harder). This, combined with their excellent surface finish is the reason they dramatically out-wear steel types. In identical running conditions, the balls in ceramic bearings exhibit less than 10% of the wear of steel balls.

There are some that think that due to their high hardness, ceramic balls are more fragile and are apt to fracture more easily than steel. That simply is not the case. Stresses typically placed on balls are compressive. Fracture failure most often occurs when parts are under tension.

Another concern by some is the difference in hardness between ceramic balls and the hardened steel races. Let us not forget that (yes, with exceptions) there is an oil film between the balls and races. The balls do not actually roll on the steel surfaces.

What makes Microblue® ceramic bearings better than ordinary ceramics?Understanding that bearings are lubricated, and MicroBlue works by changing and improving the way the lubricant "wets" the bearing surfaces (making it roll more freely), we now realize that MicroBlue is going to make any bearing better, steel or ceramic. When you combine this fact with the improvements and benefits ceramics bring to the equation, then you have the freest rolling, coolest running and longest lasting bearing ever made, period. Just ask any of our customers, that is, if they will tell you!

I’ve heard stories about failures. Why is that?
Bearing failures typically are the result of excessive RPM, lack of lubrication and/or the presence of contaminants. The result is either bearing surface breakdown and/or ball “skidding”. In respect to ceramic bearing construction, you need to be aware of the importance of the ball “fit”, or (technically) the radial play of the bearing. This is the clearance (very small) between the balls and the race. Too tight, the bearing wants to bind up. Too loose, the balls can more easily "skid" instead of roll in the races.

We're not trying to complicate things, but the intended use of the ceramic bearing dictates the desired ball/race clearance. For example, crankshaft bearings can be set up a bit "looser", due to the fact that the rotation (and forces) are in only one direction. But a go-kart front wheel bearing will see forces that are both radial (front to back) and axial (side to side) and require a tighter "fit" to avoid ball skidding. Unfortunately, measuring the clearances of a bearing is difficult without specialized equipment. At MicroBlue Racing, this priority #1, along with our exclusive use of Cerbec/Saint Gobain ceramic balls (www.cerbec.com).

Are they worth it?
There is no question that ceramic hybrid bearings are "freer rolling" than steel types, but their high cost, understandably, gives pause to many. The primary reason is the cost of the ceramic balls. The other is that they are hand-built and custom "clearanced", not mass produced. There are those who insist on "the very best" of everything, while others are not. We do our best to offer MicroBlue ceramics priced as close to the market rate for a quality bearing (not the cheap imports) as possible. Quite honestly, for those on a budget, we suggest you think about using our "Better" line of bearings, and using the money saved to give your transmission, rear-end or motor a "tune-up" instead (this combination always results in greater performance improvements, dollar-wise). You will need to decide this one!