Ceramicspeed Ceramic Coated Bearing - 61903/18

Standard steel bearings wear in a predictable way — friction climbs, efficiency drops, and eventually you're replacing them anyway. The CeramicSpeed Ceramic Coated Bearing 61903/18 interrupts that cycle by pairing steel balls with ceramic-coated races, a combination designed to reduce friction and extend service life compared to conventional steel-on-steel construction. It's a direct-fit replacement in the 61903 form factor, meaning the swap is straightforward wherever this size is spec'd.

The ceramic coating on the raceways is where the efficiency gain lives — steel balls rolling against a harder, smoother surface generate less friction than bare steel contact. CeramicSpeed positions this as an accessible step up from standard bearings, sitting below their full ceramic ball option while still delivering measurably better rolling performance over the long term. If worn or corroded bearings are costing you smoothness in your hubs or drivetrain, this is a precise, like-for-like solution.

CeramicSpeed Ceramic Coated Bearing 61903/18 Specs at a Glance

• Bearing type: Ceramic-coated races, steel balls
• Bearing size: 61903
• Inner diameter: 17 mm
• Outer diameter: 30 mm
• Width: 7 mm