Patent ID: 8851230

Claim:
A motorcycle of a type using a combustion engine as a drive source, which motorcycle comprises: an exhaust chamber having defined therein a chamber expansion compartment for exhaust gases and also having a first outer peripheral wall; and a muffler having defined therein a muffler expansion compartment for the exhaust gases and also having a second outer peripheral wall, the muffler being positioned downstream of the exhaust chamber with respect to the direction of flow of the exhaust gases, wherein the exhaust chamber is positioned between the combustion engine and a rear wheel; the first and second outer peripheral walls of the exhaust chamber and the muffler are formed by a common casing; a partition wall divides the casing in an anteroposterior direction to define the chamber expansion compartment, which is positioned forwardly of the partition wall, and the muffler expansion compartment which is positioned rearwardly of the partition wall, a rear end shape of the chamber expansion compartment and a front end shape of the muffler expansion compartment being identical with each other; the exhaust chamber has an inner side surface that is positioned inwardly of an outer side surface of the rear wheel in a motorcycle body widthwise direction; and the muffler has a rear portion that is positioned on an outer side of the rear wheel; a motorcycle body inner side end of a front wall of the muffler is positioned inwardly of the outer side surface of the rear wheel in the motorcycle body widthwise direction; and an inner side surface of the muffler includes an inclined surface gradually inclined outwardly from a front end thereof toward a rear end thereof.