Patent ID: 7290388

Claim:
A motorcycle exhaust system which comprises: a catalytic converter disposed within an exhaust passage for discharging exhaust gas from a multi-cylinder combustion engine and operable to purify the exhaust gas; and a partition plate provided on at least one of upstream and downstream sides of the catalytic converter within an exhaust pipe, forming a part of the exhaust passage, so as to extend in the direction of flow of the exhaust gas, the partition plate dividing the exhaust passage laterally; wherein an upstream end of the catalytic converter has different regions communicated with a plurality of upstream exhaust passage portions of the exhaust passage, respectively, and a downstream end of the catalytic converter is communicated with downstream exhaust passage portion or portions of the exhaust passage in a number equal to or smaller than the number of the upstream exhaust passage portions; wherein the catalytic converter has a partition wall extending in a direction conforming to a direction of flow of the exhaust gas for allowing the exhaust gas from the upstream exhaust passage portions to flow through the catalytic converter without being mixed together; and wherein the partition plate has a sectional shape taken in a direction perpendicular to the direction of flow of the exhaust gas, which shape has a corrugated portion.