Abstract: An O-ring is mounted to the wheel of a manually powered bicycle. A Teflon washer is mounted on the wheel sprocket contacting the O-ring. The friction between the O-ring and the Teflon washer are sufficient to move the crank sprocket away from dead center on a mechanism wherein the crank sprocket is rotated by manually oscillating the handle bars of the bicycle.

Abstract: A self-propelled vehicle in the form of a scooter. The vehicle includes a main frame having a platform relatively close to the ground upon which a person can stand. Forward and rearward wheels arranged in tandem ground support the vehicle with the front wheel being attached to a handle bar by which the vehicle is steered. The handle bars are journaled to the main frame in such a manner that they can be grasped by the hands and manipulated in a fore and aft direction in order to propel the vehicle along the ground, while at the same time lateral motion of the handle bars provides for the before mentioned steering. The handle bars are connected to the front wheel by a drive mechanism that includes an over-the-center apparatus which moves the handle bars off dead center each extreme reciprocation thereof.

Abstract: A bicycle has a rear wheel assembly which is chain driven by the usual foot cranked sprocket. A front wheel assembly is also chain driven by a drive sprocket supported by the front suspension and steering system. The front drive sprocket is cranked by a reciprocating connecting rod. The handlebars turn the front wheel about a vertical axis to steer the bicycle, while concurrently it can also be pivotally moved forwardly and rearwardly. One end of the connecting rod is journaled to the pivotal handlebars such that pivotal motion thereof imparts reciprocal motion into the connecting rod to crank the drive sprocket which chain drives the front wheel. A biasing means is connected to engage the connecting rod at its extreme limits of travel whereupon the rod and drive sprocket are biased from its dead center position each 180.degree.