| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a rigidity balance high in torsional rigidity and low in lateral flexural rigidity without being accompanied with increase of a vehicle weight.SOLUTION: A swing arm 30 of a motorcycle comprises: a pair of right and left front arm parts 46 extending rearward of the vehicle from a pivot part 45 which is connected to a vehicle frame; a cross part 47 connecting rear portions of the pair of right and left front arm parts 46 with each other; and a pair of right and left rear arm parts 42 extending the rearward of the vehicle from the cross part 47 to put a rear wheel 32 therebetween. A rear wheel suspension device is arranged in an opening 48 formed by the pivot part 40, the pair of right and left front arm parts 46 and the cross part 47. The pair of right and left front arm parts 46 are formed with concaves 49 curved inward in the vehicle width direction, respectively, spread outward in the vehicle width direction according as extending rearward from the respective concaves 49, pass the cross part 47 and are formed continuously to the pair of right and left rear arm parts 42, respectively.</p> |
