BigPatents India

A full cover type chain case 3 is vertically divided into a upper case 4 and a lower case 5 each of which is made of a resin. With respect to mating portions of the upper and lower cases, the outer side walls of the intermediate portions have forked portions 34, 44 into which intermediate insertion plates 23 provided on arm pipes 13a of a rear swing arm 2 are to be inserted, and the inner walls of the intermediate portions have an engagement portion including an engagement hole and an engagement claw 45. The rear end portions of the upper and lower cases are floatingly supported by screwing stepped bolts 63 passing through slots 36, 46 via ring rubber members 62 in threaded holes 25, 26 of the end piece 17.