Patent ID: 7562597

Claim:
An engine for a motorcycle, comprising: an engine case; a crankshaft rotatably supported in the engine case and extending in a width direction therein; an intermediate shaft disposed in substantially parallel to the crankshaft so as to be rotated by the crankshaft at a same speed as that of the crankshaft via a primary drive gear and a primary driven gear; a transmission input shaft disposed in substantially parallel to the intermediate shaft so as to be rotated by the intermediate shaft at a reduced speed via a secondary drive gear and a secondary driven gear; a transmission output shaft disposed in substantially parallel to the transmission input shaft so as to be rotated by the transmission input shaft at a changed speed via any combination of a plurality of transmission drive gears and transmission driven gears; a clutch unit mounted on the intermediate shaft for transmitting and interrupting rotation of the intermediate shaft to the transmission input shaft, and a balancer weight for damping engine vibration mounted on the intermediate shaft so as to be rotated integrally with the intermediate shaft.