Yamaha Hatsudoki Kabushiki Kaisha

Hidehiro Nishimura

Hiromi Suzuki

Manabu Shimoishi

Yu Motoyama

Osamu Takii

Kousei Maebashi

Junichi Ooba

Takeshi Igarashi

Toyoharu Ootsu

Takayuki Ujiie

Genichirou Hayashi

Masashi Takahashi

Keiji Sugiura

An exhaust device for a vehicle, such as a motorcycle or scooter, includes an exhaust pipe and a muffler. A first end portion of the exhaust pipe is connectable to an engine of the vehicle. A second end portion of the exhaust pipe is located within the muffler. A secondary air induction pipe supplies air to the exhaust pipe and is connected to a portion of the exhaust pipe located within the muffler. Furthermore, at least the portion of the exhaust pipe to which the secondary air induction pipe is connected is linear. A purification tube member for purifying exhaust gas forms a portion of the second end portion of the exhaust pipe.

Exhaust device and vehicle with exhaust device

An exhaust device for a vehicle, such as a scooter type motorcycle, comprises an exhaust pipe and a muffler. A first end portion of the exhaust pipe is connectable to an engine of the vehicle. The muffler includes an outer wall defining an internal space of the muffler. A second end portion of the exhaust pipe is located within the internal space of the muffler. A secondary air induction pipe supplies air to the exhaust pipe and is connected to a portion of the exhaust pipe that is within the internal space of the muffler. The secondary air induction pipe extends to the outside of the muffler via a through hole that has an edge, at least a portion of which is defined by each of a first member and a second member of the muffler.

A muffler for a vehicle, such as a scooter type motorcycle, comprises an inner tubular member and an outer tubular member. An inner surface of the outer tubular member faces an outer surface of the inner tubular member. A ring shaped or annular member is positioned between the outer surface of the inner tubular member and the inner surface of the outer tubular member. The annular member has a substantially hollow cross section and is elastically deformable in a direction perpendicular to a longitudinal axis of the inner tubular member and the outer tubular member.

Exhaust device including elastically deformable annular member and vehicle with exhaust device

A four-cycle engine is provided that includes an exhaust port for releasing combusted gas from the engine and an exhaust system. The exhaust system includes an exhaust pipe coupled with the exhaust port, a first catalyst, a second catalyst, and a secondary air introduction pipe. The first catalyst is disposed in the exhaust pipe and the second catalyst is disposed in the exhaust pipe a set distance downstream of the first catalyst. The secondary air introduction pipe is configured to introduce air into the exhaust pipe. The secondary air induction pipe is connected to the exhaust pipe between the first and the second catalysts at a location where a temperature difference of the first and the second catalysts in a cold start transient phase is within a predetermined range.

Exhaust system for an engine

A two cycle crankcase compression internal combustion engine wherein a single fuel injector is mounted in the cylinder block and can inject either directly into the combustion chamber or into the induction system through the crankcase chamber through a window in the piston. A control strategy is disclosed wherein the injection occurs primarily into the induction system during either or both of startup and low temperature.

Growing community of inventors

Shizuoka-ken, Japan

Hidehiro Nishimura