| 摘要 |
PURPOSE:To permit rearward running with slight improvement in a main transmission gear for a motor-cycle, by providing a rearward running gear train and a shift mechanism for selecting forward and rearward running between a main transmission gear including a forward running gear train only and a drive shaft of wheels. CONSTITUTION:There is provided an auxiliary transmission gear 3 for selecting forward and rearward running at a side portion of a main transmission gear 2 capable of changing engine rotation to five forward speeds, for example, so that rotation of an output shaft 24 of the auxiliary transmission gear 3 may be transmitted through a bevel gear 7 to a drive wheel. When a speed change lever 34 of a shift mechanism 40 is selected to a high speed H, for example to rotate a cam sleeve 31, the auxiliary transmission gear 3 acts to permit ratchet wheels 14 and 21 to be meshed through a fork (not shown) with pawls 13a and 20a of gears 13 and 20. Then, rotation of an input shaft 10 is transmitted through the ratchet wheel 14, gears 13 and 18, ratchet wheel 21 and gears 20, 22, 23, 12, 17 and 26 in this order, so as to permit reverse rotation (rearward running) of an output shaft 24. |
