Abstract: An exhaust muffler system for use on a motorcycle or four-wheeled vehicle provides for operation in either of two modes, a regular configuration that provides a high degree of noise reduction, or a racing specification that provides for a freer-flowing exhaust. Without changing the main body of the muffler, an operator can choose between a quieter, public road setting or a louder, high performance setting. The muffler is provided with two interchangeable spark arresters, and a main body having multiple expansion chambers therein, defined by bulkheads. When a regular spark arrester is installed, exhaust gas passes through one bulkhead three times, greatly reducing the noise produced. With the spark arrester removed, the exhaust gas passes straight through to the open air, enhancing performance. A seal is provided between the bulkheads and the spark arrester, which provides for extension or retraction in the lengthwise direction of the tail pipe.

Abstract: A reed valve includes a vibration suppressing member for suppressing transmission of vibration, caused due to opening and closing operations of a reed piece, to a fixed mounting portion of an engine part to which the reed valve is mounted. The vibration suppressing member includes an elastic annular projection formed on at least one of an outer peripheral surface of a gasket fitted around an outer peripheral edge of a valve plate and a pair of upper and lower surfaces of the gasket. The elastic annular projection is elastically engaged with the fixed mounting portion when the mount portion of the valve plate is mounted to the fixed mounting portion.

Abstract: A reed valve includes a vibration suppressing member for suppressing transmission of vibration, caused due to opening and closing operations of a reed piece, to a fixed mounting portion of an engine part to which the reed valve is mounted. The vibration suppressing member includes an elastic annular projection formed on at least one of an outer peripheral surface of a gasket fitted around an outer peripheral edge of a valve plate and a pair of upper and lower surfaces of the gasket. The elastic annular projection is elastically engaged with the fixed mounting portion when the mount portion of the valve plate is mounted to the fixed mounting portion.