An exhaust system for an off road vehicle includes a main intake pipe running in a generally longitudinal direction on the vehicle, receiving gasses from a first intake pipe for a forward cylinder and from a second intake pipe for a rearward cylinder of an mid-mounted internal combustion engine. A catalytic converter receives gasses from the main intake pipe. Instead of being mounted longitudinally, the catalytic converter extends in a transverse direction, at the rearward end of the exhaust system, behind the axis of the rear wheels. A muffler, located over the axis of the rear wheels, also extends in a transverse direction and receives gasses from the catalytic converter. The muffler outputs the gasses through a tailpipe, which is preferably above and extends wider than the main intake pipe.

An exhaust device for an engine is disposed beneath a loading platform at a position rearwardly of a seat of a utility vehicle. A plurality of exhaust pipes extend rearwardly from a front surface of an engine main body by way of one lateral side of the engine main body. The plurality of the exhaust pipes are collected by a single collecting tube. An exhaust conduit extends from the collecting tube in a direction rearwardly of the engine. A muffler is disposed in a rear portion of the vehicle and fluid connected with a downstream end of the exhaust conduit. The exhaust pipes, the collecting tube and the exhaust conduit are covered by a covering. The covering is fitted to the exhaust pipes and the exhaust conduit to thereby suppress a heat conduction from the exhaust pipes, the collecting tube and the exhaust conduit.

A vehicle having a frame and an internal combustion engine. An exhaust system extends from the internal combustion engine. The exhaust system includes an exhaust muffler with an exhaust hanger. The exhaust hanger is secured to the frame with an elastic member. An internal heat shield is located on an inner surface of the exhaust muffler to form an interior space between the internal heat shield and the exhaust muffler. The internal heat shield reduces the heat transferred to the elastic member.

A utility vehicle includes: an air-cooled engine; a cooling fan disposed on one side of the engine with respect to a vehicle widthwise direction and configured to supply a cooling air towards a cylinder unit of the engine; an exhaust pipe disposed on the other side of the engine with respect to the vehicle widthwise direction and connected with an exhaust port of the cylinder unit; an oxygen sensor fitted to the exhaust pipe; and a shield configured to prevent muddy water, which is swirled by the cooling fan, from depending on the exhaust pipe.

An engine system and method of operating the same includes a two stroke engine, an exhaust manifold coupled to the two-stroke engine, a tuned pipe coupled to the exhaust manifold coupled to the exhaust manifold, a stinger pipe coupled to the tuned pipe, a silencer coupled to the tuned pipe and an exhaust pipe, and an exhaust bypass valve. Exhaust gases are directed from the two stroke engine through an exhaust manifold and through a tuned pipe. An opening of the exhaust bypass valve is changed to redirect exhaust gases away from the tuned pipe to change a pressure within the tuned pipe. In response to changing the opening of the exhaust bypass valve, the airflow through the engine is changed.

A turbocharger and method of controlling the same includes a turbine housing comprising an inlet and an outlet, turbine wheel coupled to a shaft. The turbine housing comprising a first scroll and a second scroll for fluidically coupling the inlet and the turbine wheel. The first scroll has a first end adjacent the inlet and a second end adjacent the turbine wheel. The second scroll has a third end adjacent the inlet and a fourth end adjacent the turbine wheel. An exhaust gas diverter valve is coupled to the turbine housing restricting flow into the first scroll or the second scroll.

An engine system comprises a two stroke engine, an exhaust manifold, a tuned pipe coupled to the exhaust manifold and a turbocharger coupled to the engine. The turbocharger comprises a turbine inlet coupled to the exhaust manifold through the tuned pipe, and a turbine outlet coupled to an exhaust pipe. A silencer is coupled to the exhaust pipe. A bypass pipe has a first end coupled to the tuned pipe and a second end bypassing the turbine outlet and a wastegate disposed in the bypass pipe.

An auxiliary exhaust system for an internal combustion generator of a recreational vehicle has an elbow section with a proximal end adapted to be removably attached to an exhaust pipe of a generator and a remote end affixed to a first stack section; a second stack section adapted to be removably attached to a remote end of the first stack section, and a terminal stack section adapted to be removably affixed to a remote end of the second stack section, the stack sections together forming a fluid conduit for exhaust gases; the inlet end of the first stack section having restricted diameter portion to create a venturi effect on gases flowing through the first stack section; wherein the remote end of the elbow section is of smaller diameter than the inlet end of the first stack section and is held in concentric, spaced-apart relation to the inlet end of the first stack section to enable ambient air to be drawn into the inlet end of the first stack section as gases are passed through the auxiliary exhaust system.

An exhaust device for an engine is disposed beneath a loading platform at a position rearwardly of a seat of a utility vehicle. A plurality of exhaust pipes extend rearwardly from a front surface of an engine main body by way of one lateral side of the engine main body. The plurality of the exhaust pipes are collected by a single collecting tube. An exhaust conduit extends from the collecting tube in a direction rearwardly of the engine. A muffler is disposed in a rear portion of the vehicle and fluid connected with a downstream end of the exhaust conduit. The exhaust pipes, the collecting tube and the exhaust conduit are covered by a covering. The covering is fitted to the exhaust pipes and the exhaust conduit to thereby suppress a heat conduction from the exhaust pipes, the collecting tube and the exhaust conduit.

The present application provides a mobile selective catalyst reduction system for use at a remote location. The mobile selective catalyst reduction system may include a first trailer with an ammonia delivery system and a tempering air system mounted thereon in whole or in part and a second trailer with a selective catalyst reduction section mounted thereon in whole or in part. The ammonia delivery system, the tempering air system, and/or the selective catalyst reduction section are permanently mounted on the first trailer or the second trailer for use at the remote location.