Abstract: A bicycle propelled by stepping motion comprises a frame, forward and rear wheels, and a steering wheel. A pair of elongate pedals extend rearward from a pivot connection to the frame. An axle is mounted for rotation to the frame and has a crank arm at either end. A drive sprocket is fixed to the axle for rotation in a vertical plane, and an endless chain couples the drive sprocket to a rear wheel sprocket. Each pedal carries a connecting structure that receives an associated connecting element that extends horizontally from one of the crank arms. The connecting structure defines an arcuate path along which the associated connecting element is constrained to displace. The path is so shaped that the connecting structure engages the connecting element with a contacting surface oriented normal to the circle which the connecting element is constrained to follow by virtue of connection to the crank arm. Less force is misdirected and smoother operation is obtained.