| 摘要 |
PURPOSE:To shorten the longitudinal length of an engine and concentrate the mass of a car body by setting a speed change operating mechanism and a water pump vertically, having a supposed line connecting a crank shaft and an output shaft as boundary, and installing a supporting part for an internal combustion engine for a car body frame over or below an output shaft. CONSTITUTION:As for the internal combustion engine 13 of a motorcycle, if an input shaft 88 arranged behind a crankshaft 33 is interlocked with a gear mechanism 93, the triangular excessive spaces 119 and 120 having each large area are formed over and below the supposed line 118 connecting the crankshaft 33 and the output shaft 88 between the gear group 95 of the gear mechanism 93 which is coaxial with the output shaft 88 and the outer peripheral surface of each revolution locus of the crank shaft 33. In any case, a bulky speed change operation mechanism 97 and a water pump 107 are arranged vertically, having the supposed line 118 as boundary. Further, the supporting part 123 of the internal combustion engine 13 is positioned under the output shaft 88. Accordingly, the concentration of mass of the car body is achieved. |
