Ceramic Vs Steel Bottom Bracket

If there is one thing we see a lot in comments sections about ceramic bearings it is people claiming ceramic bearings do not offer benefits and are not.

Ceramic vs steel bottom bracket. For bottom bracket applications the maximum sustained rpm may be 130 explains lew. Ak posted by ard kessels. Quality hybrid ceramic bearings are better than steel bearings in a bicycle bottom bracket application because they have rounder balls for lower resistance better races for lower resistance and are grease efficient in low rpm low heat environments for lower resistance. Silicone nitride si3n4 grade 3 balls roll on black oxide races ground to a mirror finish after receiving magnetite and cryogenic treatments for hardness and longevity.

Ceramic bearings are in actual fact hybrid. When analyzing the individual components that contribute to the total frictional losses of a bottom bracket the frictional losses due to the seals and lubricant is greater than the frictional losses. Most sealed ceramic bearings are actually hybrid ceramic bearings which combine a steel race with ceramic ball bearings. Ceramic is not always better than steel.

Steel bearings are commodity items that are composed of hardened steel balls and a steel inner and outer race. Full ceramic bearings use ceramic races which can be lighter and provide the lowest friction but come at a durability cost. The ceramic balls are often silicon nitride or equivalent. Ceramic bottom brackets ceramic oversized derailleur pulleys tools and accessories ceramic bearings vs.

Which ones do you need. Bottom bracket efficiency is based on the design and the quality of materials not necessarily on the type materials i e ceramic vs. Ceramic bearing equipped bottom brackets or hybrid ceramics to be more precise are generally much more expensive than their stainless. A bb30 bottom bracket that uses ceramic bearings will weigh 3 5 grams less than its stainless steel counterpart.