Patent ID: 8746429

Claim:
An improvement for a clutch system that conveys rotational energy from a power source to a gearbox input shaft of a motorcycle, the clutch system of the type having a clutch basket having a plurality of longitudinally-parallel slots formed in an outer wall thereof, the clutch basket mechanically coupled to the power source; a plurality of annular, pronged clutch drive plates each having a plurality of prongs projecting radially away from an outer peripheral edge, each prong adapted for slidable engagement within one of the slots of the clutch basket such that the pronged clutch drive plates are rotationally coupled to the clutch basket and slidably moveable along a common longitudinal axis thereof; a plurality of annular, splined steel driven plates sandwiching each of the pronged clutch drive plates and including a plurality of splines projecting inwardly from an inner edge thereof; a clutch hub having peripheral teeth adapted for slidable engagement with the splines of each splined steel driven plate, the clutch hub rotationally coupling each of the splined steel driven plates mutually together, the clutch hub including a central splined aperture therein for engaging the gearbox input shaft of the motorcycle, the clutch hub further including a plurality of post apertures between the central aperture and the peripheral teeth; an annular backing plate having a plurality of post apertures therein, and a plurality of posts that traverse the apertures of the clutch hub and baking plate; the improvement comprising: a pressure plate having a plurality of splines projecting inwardly from an inner edge of a first side thereof and adapted to slidably engage the clutch hub therewith, a plurality of post apertures traversing therethrough, and a pneumatic cylinder cradle on a second side thereof; and a pneumatic piston sandwiched between a pneumatic cylinder cap having a pneumatic cylinder therein and the second side of the pressure plate, the cylinder cap including an air aperture therein for introducing pressurized air into the pneumatic cylinder of the cylinder cap for driving the piston against the pressure plate; the pneumatic cylinder cap, piston, pressure plate, clutch hub, clutch drive plates, and backing plate all mutually fixed by the plurality of posts traversing the apertures of the cylinder cap, pressure plate, clutch hub, and backing plate; whereby with the power source spinning the clutch basket and pronged clutch drive plates, when air is introduced into the pneumatic cylinder the piston presses against the pressure plate to press the splined steel driven plates against the pronged clutch drive plates and the backing plate to cause the splined steel driven plates to rotate therewith, rotating the clutch hub to convey rotational energy to the gearbox input shaft of the motorcycle.