Abstract: A motorcycle accommodates an enlarged rear tire by interposing an intermediate shaft between the transmission output gear and the rear wheel drive gear. The intermediate shaft includes a power input gear disposed in the same vertical plane as the transmission output gear, and a first drive belt couples the two together. The intermediate shaft also includes a power output gear disposed in the same vertical plane as the rear wheel drive gear, and a second drive belt couples the two together. The first vertical plane lies closer to the central longitudinal axis of the support frame than does the second vertical plane, allowing the center of mass of the engine and transmission to be maintained substantially along the central longitudinal axis. When incorporated into a soft-tail type motorcycle frame, the intermediate shaft is coincident with the pivot axis of the soft-tail suspension.

Abstract: A motorcycle accommodates an enlarged rear tire by interposing an intermediate shaft between the transmission output gear and the rear wheel drive gear. The intermediate shaft includes a power input gear disposed in the same vertical plane as the transmission output gear, and a first drive belt couples the two together. The intermediate shaft also includes a power output gear disposed in the same vertical plane as the rear wheel drive gear, and a second drive belt couples the two together. The first vertical plane lies closer to the central longitudinal axis of the support frame than does the second vertical plane, allowing the center of mass of the engine and transmission to be maintained substantially along the central longitudinal axis. When incorporated into a soft-tail type motorcycle frame, the intermediate shaft is coincident with the pivot axis of the soft-tail suspension.

Abstract: A motorcycle frame is formed of tubular members which are hollow to provide a reservoir for oil used to lubricate the motor of the motorcycle. Fittings are provided within the tubular frame for receiving an oil filler cap, an oil spill hole, an outlet to the oil pump, an oil return inlet, an oil drain, and a crankcase vent. The seating area of the motorcycle frame is dropped closer to the ground due to the elimination of the oil reservoir normally located below the seating area of the frame, while incorporating a dampened rear wheel swing arm frame.