US Patent 7766123 Vehicle exhaust system

An exhaust system for a vehicle, such as a motorcycle or other straddle-type vehicle, that achieves miniaturization while providing advantageous noise reduction characteristics. The exhaust system is associated with an engine of a vehicle and includes an exhaust pipe connected to the engine and a silencer. A conical member is positioned within the silencer and includes an upstream end and a downstream end. At least a portion of a side wall of the conical member includes a plurality of through-holes. The conical member is oriented such that a radial dimension of the conical member increases in a direction from the upstream end to the downstream end.