Bottom brackets

Shimano Shimano BB-UN300 Bottom Bracket

BSA 68 mm · 110 mm spindle

Compatibility: reviewed
Known specifications can be used by the compatibility engine.

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Technical review
Jul 28, 2026
Compatibility review
Reviewed Jul 28, 2026

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Technical data

Specifications

Supported BB shells
BSA-68
Supported crank spindles
Square Taper
Spindle length
110 mm