an anti - theft bicycle pedal is disclosed . the mounting end of the pedal is shaped with polygonal faces and / or splines to match an opening on the crank so that when the mounting end of the pedal axle is inserted into the matching opening and locked into place , the pedal cannot be removed without an unlocking agent . with an unlocking agent , the pedal is easily removed without tools . the pedal can be reversibly mounted on the crank so that the bicycle cannot be pedaled away , or so that the pedal can be stowed during transport or storage . the pedal cannot rotate in the crank as a result of polygonal faces and / or splines on the mounting end that resist rotation . a physical stop can be used to control the symmetry of insertion into the opening which facilitates reversible mounting .