An exhaust gas purification device is disposed in an exhaust passage of an engine disposed in an engine room defined in a hull, and is configured to remove at least a nitrogen oxide from an exhaust gas discharged from the engine. The exhaust gas purification device includes: a catalytic part including a selective reducing catalyst for selectively reducing the nitrogen oxide; a reducing agent addition device configured to add a reducing agent to the exhaust gas on an upstream side of the catalytic part in a flow direction of the exhaust gas; and a casing configured to contain the catalytic part. At least a part of the casing is disposed inside the engine room.

An exhaust device for an internal combustion engine of a saddled vehicle includes an exhaust muffler disposed on an outer side of a rear wheel so as to overlap the rear wheel when viewed from a side a muffler protector which covers the muffler. The muffler protector includes an inner protector half body covering the exhaust muffler from the rear wheel side and an outer protector half body covering the exhaust muffler from a vehicle outer side opposite to the rear wheel The inner protector half body is detachably mounted on the exhaust muffler or the outer protector half body while maintaining a state in which the outer protector half body is mounted on the exhaust muffler.

An exhaust manifold for use with an internal combustion engine, the exhaust manifold including a body, one or more fluid passageways defined by the body, a valve in fluid communication with at least one of the one or more fluid passageways, the valve being adjustable between an open configuration and a closed configuration, a mounting bracket supported by the body, and an actuator in operable communication with the valve and configured to adjust the valve between the open and closed configurations, and wherein the actuator is coupled to the mounting bracket.

A straddle-type vehicle includes a driver seat on which a driver rides, a cylinder head of an engine arranged in a region in front of and below the driver seat, an exhaust pipe that is connected to an exhaust port formed on a front surface of the cylinder head and exhausts exhaust of the engine, and a control unit that is arranged in an engine front space formed in front of the cylinder head, above the exhaust pipe, and below an upper end surface of the engine and controls the straddle-type vehicle.

An exhaust device for guiding exhaust gas from an exhaust pipe in front of an engine to a muffler in a rear of the engine is provided. The exhaust device includes a catalyst case in which a catalyst configured to purify the exhaust gas that passes through the exhaust pipe is accommodated, and a chamber in which a muffling chamber configured to reduce an exhaust noise is formed downstream of the catalyst case. The catalyst case is disposed in a range from a front space with respect to the engine to a front part of a lower space of the engine. The chamber is disposed so as to occupy at least a rear part of the lower space of the engine.

An exhaust device that guides exhaust gas from an exhaust pipe in front of an engine to a muffler in a rear of the engine is provided. The exhaust device includes a primary catalyst case accommodating a primary catalyst configured to purify the exhaust gas at a downstream side from the exhaust pipe, a secondary catalyst case accommodating a secondary catalyst configured to purify the exhaust gas at a downstream side from the primary catalyst, and a chamber formed with a muffling chamber configured to reduce an exhaust noise at a downstream side from the secondary catalyst. The primary catalyst case is disposed in a front space of the engine. The secondary catalyst case is disposed on a front part of a lower space of the engine. The chamber is disposed so as to occupy at least a rear part of the lower space of the engine.

An exhaust device in which an exhaust passage wraps around from a front side of an engine to a lower side of the engine and extends to a rear side is provided. The exhaust device includes a catalyst configured to purify exhaust gas in the exhaust passage and disposed in front of the engine, and a gas sensor disposed on a wall surface of the exhaust passage at an upstream side than the catalyst. The gas sensor is disposed in front of the engine so as to be directed toward the engine.

The invention relates to an exhaust gas aftertreatment system for an internal combustion engine (10), in particular for an internal combustion engine (10) which is charged by means of a turbocharger (30) and spark-ignited by means of spark plugs (16). A particulate filter (24) and an electrically heatable three-way catalytic converter (26) downstream of the particulate filter (24) are arranged in a position close to the engine in an exhaust gas system (20) connected to an outlet (12) of the internal combustion engine (10). A further three-way catalytic converter (28) is arranged in the underbody position of the motor vehicle downstream of the electrically heatable catalytic converter (26). According to the invention, the electrically heatable three-way catalytic converter (26) is heated electrically after engine start, and the particulate filter (24), the electrically heatable three-way catalytic converter (26) and the further three-way catalytic converter are additionally heated by the exhaust gas flow from the internal combustion engine (10). The electric heating of the electrically heatable three-way catalytic converter (26) is switched off when the electrically heatable three-way catalytic converter (26) has reached its light-off temperature.

A vehicle underbody structure includes a catalyst disposed in a front portion of an exhaust pipe; a cover member for covering the catalyst from above; and a heat insulator disposed inside a tunnel portion behind the catalyst and configured to cover the exhaust pipe from above. The heat insulator is disposed away from the tunnel portion by a predetermined gap in an up-down direction. A front portion of the heat insulator and a rear portion of the cover member are disposed in such a way as to overlap each other. A front end of the heat insulator is disposed on the upper side with respect to a rear end of the cover member.

A saddle-riding type vehicle exhaust structure includes: an exhaust pipe that is connected to an exhaust port connecting to a combustion chamber of an engine and has a circular cross-sectional shape which is orthogonal to an exhaust flow direction; and a muffler that is connected to a downstream side in the exhaust flow direction of the exhaust pipe, wherein the exhaust pipe includes a muffler connection part that is connected to the muffler, an exhaust pipe upstream part that is connected to an upstream side in the exhaust flow direction of the muffler connection part, and an exhaust pipe downstream part that is connected to a downstream side in the exhaust flow direction of the muffler connection part, a cross-sectional area that is orthogonal to the exhaust flow direction of the muffler connection part is larger than each of a minimum value of a cross-sectional area that is orthogonal to an exhaust flow direction of the exhaust pipe upstream part and a minimum value of a cross-sectional area that is orthogonal to an exhaust flow direction of the exhaust pipe downstream part, and a vehicle width direction size of the cross-sectional shape of the muffler connection part and a vertical direction size of the cross-sectional shape of the muffler connection part are different from each other.