An improved bicycle crankshaft assembly, including a crank axle with an axial axis, a first axle end, and a second axle end axially opposed to the first axle end; a first crank arm connected to the crank axle at a first crank arm interface adjacent the first axle end; a second crank arm connected to the crank axle at a second crank arm interface axially spaced from the first crank arm interface; a first bearing surrounding said crank axle adjacent said first axle end for rotation of said crank axle about said axial axis; a second bearing surrounding the crank axle and axially spaced from the first bearing. The crank axle includes reinforcement fibers for structural reinforcement of the crank axle and the crank axle is an integral crank axle that extends through the first bearing and the second bearing.