Patent ID: 6405821
Filing Date: 2002-06-18
Classification: B62K,F02B,F02F

Abstract:
A power unit of a motorcycle comprising:an engine unit in which a counter shaft rotating, while interlocking with a crankshaft, is supported in parallel at a rear portion in a casing of an engine body provided with the crankshaft disposed along a width direction of a motorcycle body and a bracket portion having a fitting hole extending rearward so as to pass through in the width direction of the motorcycle body is formed in a rear portion outside the casing; a transmission unit in which an input shaft and an output shaft are pivoted at front and rear portions in another casing different from the casing of the engine unit so as to constitute a transmission device; and a bevel unit receiving a bevel input shaft disposed along the width direction of the motorcycle body, a bevel output shaft disposed along a longitudinal direction of the motorcycle body and a bevel gear which are all disposed in a further casing so as to take out an engine output rearward from the bevel output shaft, wherein one side surface of a front portion, in the longitudinal direction of the motorcycle body, of the transmission unit is fixed to one side surface of a rear portion of the casing in the engine unit so as to connect the counter shaft to the input shaft to be integrally rotatable, a bearing boss of the output shaft is closely fitted to the fitting hole in the bracket portion with one side surface of the rear portion of the transmission unit being disposed adjacent to one side surface of the bracket portion of the engine unit, and the bearing boss of the bevel input shaft is closely fitted and fixed to the fitting hole of the bracket portion with the bevel unit being disposed adjacent to another side surface of the bracket portion so as to connect the output shaft to the bevel input shaft to be integrally rotatable.