US Patent 7503239 Bicycle crank arm assembly

A bicycle crank arm assembly is provided with a bicycle crank arm with a first end configured to be coupled to an axle of a bottom bracket and a second end with a pedal attachment bore for receiving a bicycle pedal shaft. A tubular member is press fitted into the bore of the bicycle crank arm. The tubular member has an external circumferential with serrations that is surface non-releasably press fitted into the pedal attachment bore of the bicycle crank arm, and an internally threaded surface adapted to be coupled to the bicycle pedal shaft. The crank arm preferably has a counterbore at one axial end of the pedal attachment bore with a washer disposed therein such that the washer partially overlaps the tubular member.