This bottom bracket cup set is a superb choice for anyone who appreciates legendary Chris King precision machining pared with supremely smooth ceramic bearings. The Chris King Ceramic Bottom Bracket for Shimano mountain is the same as their stainless steel bottom bracket but has ceramic balls in place of stainless steel. By now, virtually everybody knows Ceramic bearings are lighter, harder and have a higher level of roundness versus stainless balls for a bearing with exceptional speed and strength.
The bottom bracket is constructed from precision machined, anodized alloy cups fitted with 24 ceramic bearings. These bearings can have grease purged and injected with Chris King's BB Grease Injection Tool just like the stainless steel bearings. So essentially, they are sealed bearing that are serviceable. Quite possibly the best mountain bottom bracket available.
Threads on the cups are absolutely perfect, so they will install to your frame without issue. Center sleeve is attached to the cups with O-ring seals and succeeds in keeping dirt and condensation out of the bottom bracket assembly. The total weight is 101 grams including 85 grams for the cups and bearings, 8 grams for the spacers and 8 grams for the sleeve.
These BB's are compatible with Shimano outboard cranksets only and will not work with SRAM/Truvativ GPX or FSA cranksets.