An exhaust manifold comprises a plurality of exhaust intake conduits structured to be fluidly coupled to an engine and receive exhaust gas from a corresponding cylinder of the engine. At least one exhaust intake conduit provides a reduction in an exhaust intake conduit cross-sectional area from an inlet to an outlet. A plurality of bends are each defined by a respective one of the exhaust intake conduit outlets. An exhaust intake manifold is fluidly coupled to the exhaust intake manifold and defines an exhaust intake manifold flow axis. Each of the plurality of bends is shaped so as to define n angle of approach of exhaust gas flowing therethrough. A first angle of approach of the first bend relative to the exhaust intake manifold flow axis is smaller than a second angle of approach of an inner second bend.

Substances in external EGR gas are smoothly guided to a combustion chamber. An intake passage includes: a main intake passage including intake ports and communicating with a combustion chamber and having a supercharger interposed in the main intake passage; and a bypass passage branching off from the main intake passage upstream of the supercharger, and connected downstream of the supercharger; a flow rage adjustment valve changing a cross-sectional flow area of the bypass passage. The bypass passage is provided above the main intake passage, and includes an upper passage to which an EGR passage is connected.

An air intake structure of a saddle riding vehicle disposed on a saddle riding vehicle that includes intake system components above an engine, the engine includes a plurality of cylinders aligned at least in front and rear, the intake system components include: funnels coupled to intake ports of the respective cylinders; and injectors facing openings of the respective funnels, the funnels and the injectors are arranged inside the air box, the air intake structure includes an air filter in a front side with respect to the funnel and the injector disposed in a cylinder in a front side. In the air intake structure of a saddle riding vehicle, the air filter is at least disposed so as to be oriented in a vertical direction in side view, and the air filter has a middle part on which a louver is disposed.

An air intake apparatus includes an air intake apparatus body including an intake passage and a detection bore, a sensor holding portion holding a sensor, a pipe member constituted by an elastic member and including a first end and a second end, the first end being connected to the detection bore and the second end being connected to the sensor holding portion, the sensor holding portion including a fitting portion which includes an inner peripheral portion contactable with an outer peripheral portion of the second end, the sensor and the pipe member being fixed to the sensor holding portion by a contact of the outer peripheral portion of the second end with the inner peripheral portion of the fitting portion in a state where an insertion portion of the sensor is inserted to be positioned within the second end of the pipe member to widen the second end.

A convergent nozzle is in a mixer housing and in a flow path from an air inlet of the mixer to an outlet of the mixer. A convergent-divergent nozzle is in the mixer housing and includes an air-exhaust gas inlet in fluid communication to receive fluid flow from the convergent nozzle and from the interior of the exhaust gas housing. A first nozzle module is configured to be received in the mixer housing and, when received in the mixer housing, define at least a portion of the convergent nozzle or the convergent-divergent nozzle. A second nozzle module is configured to be received in the mixer housing separate from the first nozzle module. The second nozzle module, when received in the mixer housing, is configured to define at least a portion of the convergent or the convergent-divergent nozzle. The second nozzle module has a different flow characteristic than the first nozzle module.

An exhaust manifold comprises a plurality of exhaust intake conduits structured to be fluidly coupled to an engine and receive exhaust gas from a corresponding cylinder of the engine. At least one exhaust intake conduit provides a reduction in an exhaust intake conduit cross-sectional area from an inlet to an outlet. A plurality of bends are each defined by a respective one of the exhaust intake conduit outlets. An exhaust intake manifold is fluidly coupled to the exhaust intake manifold and defines an exhaust intake manifold flow axis. Each of the plurality of bends is shaped so as to define an angle of approach of exhaust gas flowing therethrough. A first angle of approach of the first bend relative to the exhaust intake manifold flow axis is smaller than a second angle of approach of an inner second bend.

An intake apparatus includes an intake manifold, an EGR gas distributor, and an EGR cooler. The intake manifold includes a surge tank and branch pipes. The EGR gas distributor includes a gas inlet, a gas chamber, and gas distribution pipes connected to the branch pipes. The branch pipes are each formed with a connecting hole for the gas distribution pipes. The EGR cooler is provided adjacent to the gas chamber to warm the inside wall of the gas chamber and includes a hot water passage and a gas passage. The gas chamber and the hot water passage are arranged to traverse the branch pipes. The gas distribution pipes are connected to the corresponding connecting holes. The EGR gas distributor and the EGR cooler in an integrated form are attached to the intake manifold.

An intake duct structure of a motorcycle includes front forks disposed on both of right and left sides of a head pipe of a body frame and a main frame extending obliquely backward and downward from the head pipe, wherein the intake duct structure extends from a front end of the motorcycle toward the head pipe and is formed in such a manner that an interfered area where a rotational orbit of the front forks at a time of steering overlaps the intake duct structure is elastically deformable.

An air intake structure of a saddle riding vehicle disposed on a saddle riding vehicle that includes intake system components above an engine, the engine includes a plurality of cylinders aligned at least in front and rear, the intake system components include: funnels coupled to intake ports of the respective cylinders; and injectors facing openings of the respective funnels, the funnels and the injectors are arranged inside the air box, the air intake structure includes an air filter in a front side with respect to the funnel and the injector disposed in a cylinder in a front side. In the air intake structure of a saddle riding vehicle, the air filter is at least disposed so as to be oriented in a vertical direction in side view, and the air filter has a middle part on which a louver is disposed.

An intake device for an internal combustion engine configures a flow passage for intake air that is drawn into combustion chambers. The intake device includes an intake manifold configuring multiple runners that respectively distribute intake air to multiple cylinders, a surge tank including a cavity that is connected to the runners and defines a convergence portion, a throttle body incorporating a throttle valve, and a connection pipe connecting the surge tank and the throttle body and configuring a curved flow passage extending between the throttle body and the surge tank. The connection pipe includes a partition plate that divides the curved flow passage into a circumferentially inner flow passage and a circumferentially outer flow passage.