Crankhd

In internal combustion engines, the crankshaft is the "backbone" that converts linear piston motion into rotary motion to drive the wheels.

: Common on older American-made bikes and children's BMX bikes. A single piece of forged steel forms both arms and the axle. CrankHD

A bicycle crank is the lever that connects the pedals to the bottom bracket, turning your pedaling effort into rotational motion to drive the chain. In internal combustion engines, the crankshaft is the

: The most standard modern setup, consisting of a left arm, a right arm, and a separate spindle . They typically use square-taper or splined (like Shimano Octalink) interfaces. A bicycle crank is the lever that connects

: In this design, the spindle is permanently attached to one of the crank arms (usually the drive side), simplifying installation and increasing stiffness. Engine Crankshafts