Vehicle exhaust system

Abstract

An exhaust system for a straddle-type vehicle, such as a motorcycle, that is compact while also reducing noise output. The exhaust system communicates with an engine of an associated vehicle. The exhaust system includes an exhaust conduit, which is at least partially defined by an exhaust pipe, communicating with a combustion chamber of the engine. The exhaust system also includes a silencer. A ratio of a volume of the silencer to a volume of the exhaust conduit is between about 0.7 to 1.4. In some arrangements, the volume of the silencer and the volume of the exhaust conduit are substantially equal to each other.

Description

RELATED APPLICATIONS [0001] This application is related to, and claims priority from, Japanese Patent Application No. 2007-031097, filed Feb. 9, 2007 and Japanese Patent Application No. 2006-092334, filed Mar. 29, 2006, the entireties of which are incorporated by reference herein and made a part of the present specification. Application Ser. Nos. ______ (Attorney Docket FY.53109US2A), ______ (Attorney Docket FY.53109US3A), and ______ (Attorney Docket FY.53109US4A), entitled VEHICLE EXHAUST SYSTEM, all filed on even date herewith, are also incorporated by reference herein in their entireties and made a part of the present specification. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention generally relates to an exhaust system for a vehicle. More particularly, the present invention relates to an exhaust system for a straddle-type vehicle and a straddle-type vehicle incorporating such an exhaust system. [0004] 2. Description of the Related Art [000...

AI Technical Summary

Benefits of technology

The patent text describes an exhaust system for motorcycles that is designed to be both efficient and accommodate the vehicle's physical constraints. The challenge is to achieve both high performance and low weight in a compact space while maintaining smooth handling characteristics. The text also discusses the impact of noise regulations and the weight of certain components on the motorcycle's handling characteristics. The text describes various embodiments of the exhaust system that address these challenges. The technical effects of the invention include achieving a smaller size of the exhaust system while maintaining high efficiency and noise reduction, as well as reducing the impact of noise regulations on the vehicle's handling characteristics.

Problems solved by technology

However, such an exhaust system is not well accommodated in a vehicle body of a motorcycle.

Normally, a muffler having an ideal length in terms of engine performance is only seldom accommodated intact in a configuration of a motorcycle and, as compared with design of a muffler for four-wheel passenger cars, the design of a motorcycle exhaust system to meet both performance and physical constraints is significantly more challenging.

That is, it is difficult in the context of a motorcycle exhaust system to achieve a length of the exhaust system that will both provide desired performance attributes and be accommodated within the space constraints of a motorcycle while maintaining a configuration that is as smooth as possible.

Moreover, because certain components of the exhaust system (e.g., the silencer) are usually located at a distance from a center of gravity of the motorcycle, the adverse influence of excess weight of the exhaust system on the handling characteristics of the motorcycle is increased.

Moreover, when a metallic sheet from which the silencer is constructed is thin, it vibrates thereby increasing noise.

To avoid such a situation, the silencer is by all means liable to be relatively large in weight.

An increase in the weight of the silencer results in undesired handling characteristics of the associated motorcycle.

In this manner, since a structure of an exhaust system for motorcycles is determined in terms of a variety of interrelated factors, it has been extremely difficult to realize an exhaust system in which miniaturization is achieved and a desired exhaust efficiency and noise-reduction characteristics are met.

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