FSA Headset Bearing, 40 x 51.8 x 8mm, Stainless Steel, ACB, 1.5″ x 36/45 (MR127)

A precision angular contact bearing (ACB) for FSA headsets, machined to the 40 x 51.8 x 8mm MR127 size used across a wide range of road and mountain bike headsets. Replacing a worn or gritty headset bearing restores smooth, play-free steering.

Built with a stainless steel race and ball set, it’s designed to shrug off road grime and moisture while holding its contact angle under load. A straightforward drop-in fix for a headset that’s started to feel notchy.

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