An engine includes a combustion chamber, a cylinder head, an intake valve, a partition wall plate, and a tumble valve. The cylinder head includes an intake port that communicates with the combustion chamber. The intake valve includes a head configured to open and close an open end of the intake port. The partition wall plate partitions the intake port into first and second passages. The tumble valve is configured to open and close either one of the first passage and the second passage. A cross sectional shape of the partition wall plate is defined on a basis of a shape of a gap that is surrounded by a contour of the head and a contour of the open end, as viewed in a reference direction. The reference direction is a direction from a reference point in the intake port to a gap between the open end and the head.

Provided herein is a fluid duct 2 comprising a tubular base wall 11 surrounding a duct channel and at least one bellows 10 formed along a section of the tubular base wall 11. The bellows 10 comprises a plurality of convolutes 12 having a profile 14 projecting radially from the base wall 11. At least one convolute 12 wraps around the duct channel at a wrap-around angle Ω of between 180° and 720° from a first end 22a to a second end 22b of the convolute 12, said second end 22b being offset in a flow direction F parallel to a centerline C of the duct channel by a non-zero offset distance D from the first end 22a.

A sensor support portion supports a physical quantity sensor. A flow path housing portion forms a measurement flow path, which accommodates a support tip end portion of the sensor support portion. The sensor support portion includes a support front surface, which includes a front fixed portion away from the support tip end portion and fixed to an inner surface of the flow path housing portion. The physical quantity sensor includes a sensor exposure surface exposed from the support front surface. A separation distance between an end portion of the front fixed portion and an end portion of the sensor exposure surface is smaller than a separation distance between the end portion of the sensor exposure surface and the support tip end portion.

A fuel feed unit has a base body with an intake channel section, into which a fuel opening opens. A partition wall section divides the intake channel section into a mixture channel and an air channel. The wall section has a recess in which the throttle flap at least partially lies in an end position. The wall section has, upstream of the recess, a continuous surface facing the mixture channel and which has lateral sections adjacent to the channel wall and a middle section running between the lateral sections. The lateral sections have, upstream of the throttle flap, a separation edge for the flow. In the end position, the side of the throttle flap facing the mixture channel defines a reference plane which divides the unit into a first region and a second region. The lateral sections extend, at least directly upstream of the recess, into the second region.

Gas admission valve assembly includes a housing, an elongated valve guide disposed within a central bore of the housing, a valve including a valve stem slidably disposed within the valve guide and a valve head selectively engagable with a valve seat of the housing to control flow between gas entry and exit openings into a housing entry chamber. First and second stem seals are disposed at opposite ends of the valve guide in sealing engagement with the valve stem between the valve stem and the central bore of the housing distally and the valve guide proximally.

A dual purge system for a vehicle includes an ejector including a drive inlet section connected to a first end of a main body section, a suction inlet section connected to a first side of the main body section, an outlet section coupled to an intake passage section, a nozzle section, and a diffuser, wherein the diffuser communicates with internal passages of the main body section and the outlet section and has a larger passage cross-sectional area than a channel cross-sectional area of an outlet of the nozzle section, wherein a driving fluid flows through the drive inlet section, in response to a negative pressure being produced in the main body section by the driving fluid, the suction inlet section suctions a fuel evaporation gas from a canister, and the outlet section discharges the driving fluid and the fuel evaporation gas.

There is provided an intake device, in which an air cleaner is disposed behind an engine and which is configured such that air is introduced from the air cleaner to the engine through an intake passage. The intake device includes: a pressure sensor configured to detect a pressure in the intake passage; a throttle body that forms an upstream side of the intake passage; and an intake pipe that forms a downstream side of the intake passage. An attachment portion to which the pressure sensor is attached is formed on an outer peripheral surface of the intake pipe.

A system for enhancing performance of a carburetor engine and peripherals of an all-terrain vehicle.

Systems and apparatuses include a system including an electronic compressor, a bypass intake coupled between an engine system of a generator set and the electronic compressor, a bypass outlet coupled between the electronic compressor and the engine system, and a valve positioned to selectively inhibit flow between the bypass intake and the bypass outlet during a starting operation.

A measurement control device includes a sensing unit and a low-pass filter unit. The sensing unit outputs an air flow rate value corresponding to an air flow rate flowing through a flow path. The low-pass filter unit removes high-frequency components included in the air flow rate value input from the sensing unit. The measurement control device calculates a pulsation state that is a state of a pulsation occurring in the air flow rate based on the air flow rate value that has passed through the low-pass filter unit. The measurement control device corrects the air flow rate value using the pulsation state.