US Patent 7484361 Exhaust gas purifying apparatus of motorcycle

An exhaust gas purifying apparatus is provided for a motorcycle, configured to minimize engine output characteristics, and to raise the temperature of a catalyst to an activation temperature rapidly after a start of the engine, while not increasing a vehicle body size. The motorcycle includes an engine in which a cylinder block is extended upward on a crankcase. An exhaust port is provided on a front portion of the engine; an exhaust pipe extends forward of the engine from the exhaust port, then extends downward once, and thereafter, extends toward the rear of a vehicle body. A catalyst is placed in the exhaust pipe. The exhaust pipe passes along a side of the cylinder block, and the catalyst is placed in the exhaust pipe in a position located on the side of the cylinder block.