| 摘要 |
<p>A power transmission unit for a motorcycle is disclosed which includes a power unit case (3) consisting of a crankcase and a transmission case both of which are integrally formed with one another. A bevel gear case (20) incorporating therein a bevel gear assembly is detachably secured to the power unit case at a recessed section (6) of the latter. The recessed section is located rearwardly of a generator (5) which is disposed at the outermost part of the power unit case. The bevel gear assembly comprises a driving bevel gear (17) connected with a countershaft (13) in the power unit case, and a driven bevel gear (18) connected with a final shaft (29) which is in turn connected to a rear wheel (Wr). Both the driving and driven bevel gears are rotatably supported in the bevel gear case by means of bearings (15 and 30, 31 respectively) received in bearing holders (23, 24 and 20a, 32 respectively) which are detachably secured to the bevel gear case by means of tightening bolts (22 and 34 respectively), whereby the bevel gear case is mounted on or dismounted from the power unit case with the driving and driven gears incorporated in the bevel gear case.</p><p>. A motorcycle having the unit fitted thereto is of minimum transversal width, both the driving and driven bevel gears are easily assembled and disassembled in the bevel gear case and the whole unit is easily mounted and dismounted on the motorcycle.</p> |
