Abstract: An adjustable crank assembly is provided. The adjustable crank assembly includes a crank arm having a surface with a plurality of notches, and a retention block that partially houses the crank arm and allows the crank arm to slide along an axis relative to the retention block. The retention block includes a clamping block and a locking pin, both of which being adapted to selectively engage the crank arm when the retention block is placed in a locked position, and a locking lever for transitioning between a locked position and an unlocked position. The locking lever provides a compressive force to the clamping block when placed in a locked position and a retracting force to the locking pin when placed in an unlocked position.