FC-M590 36T Black Middle 104BCD

This 36-tooth middle chainring comes from Shimano's Deore FC-M590 series, a 9-speed triple crankset built around a 104mm bolt circle diameter and a 4-arm mounting pattern. Finished in black, it sits between the outer 48T and inner 26T rings on the original 48-36-26T setup, giving riders a direct replacement for worn factory rings on this popular Deore groupset.

Beyond the FC-M590, this ring is cross-compatible with several other Shimano 9-speed triple cranksets sharing the same 104mm middle-ring bolt pattern, including Deore FC-M591, Alivio FC-M4060 and FC-T4060, and Acera FC-M391 and FC-T3010. It offers a practical service option for shops and home mechanics maintaining older 9-speed mountain and trekking drivetrains without sourcing a full crankset.

Quick Facts