Abstract: A bicycle rear suspension mechanism imparts a forward movement inducing moment about the axis of the rear wheel during the operation of the suspension mechanism. A parabolic swing arm is mounted such that the axis of rotation of the rear wheel is positioned proximate to the vertex, and preferably in alignment with the central axis, of the parabolic shape. A flexor element is formed into the perimeter of the parabolic swing arm at a location below the central axis of the parabolic shape and below and forwardly of the rear wheel axle. A shock absorber can be connected to the upper rocker arm to dampen the operation of the suspension mechanism. The release of stored energy in the flexor element directs a resultant force offset by a moment arm from the axis of rotation of the rear wheel to contribute to the forward momentum of the bicycle.