There is provided an air cleaner including: an outlet pipe through which air is discharged; an airflow meter that is inserted toward an interior of the outlet pipe through a wall of the outlet pipe; and a flow-regulating member that is formed projecting from an inner surface of the outlet pipe at a side of the airflow meter, the flow-regulating member including an edge that is formed with a peaked shape with respect to the inner surface and that runs along a direction of flow of air, a rear end that is formed at a downstream end of the edge in the direction of flow, and that is shaped cut sharply toward the inner surface and a width-narrowing portion that decreases in width in a circumferential direction of the outlet pipe on progression downstream in the direction of flow.

There is provided an air cleaner including: an outlet pipe through which air is discharged; an airflow meter that is inserted toward an interior of the outlet pipe through a wall of the outlet pipe; and a flow-regulating member that is formed projecting from an inner surface of the outlet pipe at a leading end side of the airflow meter, the flow-regulating member including an edge that is formed with a peaked shape with respect to the inner surface and that runs along a direction of flow of air, a rear end that is formed at a downstream end of the edge in the direction of flow, and that is shaped cut sharply toward the inner surface and a width-narrowing portion that decreases in width in a circumferential direction of the outlet pipe on progression downstream in the direction of flow.

An air intake duct (50) for a motorcycle supplies air taken in through an air inlet (24) in a front portion of a vehicle body to an engine (E) located at a center portion, in a longitudinal direction of the motorcycle, of the vehicle body. The air intake duct (50) includes a duct front (69) having the air inlet (24) formed at a front end thereof, and a duct body (70) removably coupled to a rear end portion of the duct front (69). The duct body (70) extends in the longitudinal direction so as to pass through an outer lateral side of the engine (E) and is removably connected at a rear end portion thereof to an air cleaner (40). In a state in which the duct body (70) is removed from the air cleaner (40), a cleaner element (87) can be attached and removed.

An engine includes an air filter assembly having a filter element and a case. A base of the case includes multiple clips, multiple pins, and a catch. The clips are configured to engage a bottom wall of the filter element. A cover of the case includes multiple hinge wings, a hook, and a guide structure. Each of the hinge wings is coupled with a corresponding pin of the base to allow the cover to rotate about the pins. The hook is configured to fasten to the catch of the base for securing the case in a closed configuration. The guide is configured to facilitate placement of the hook and prevent lateral slipping of the hook from the catch of the base. The base and the cover define an interior volume of the air filter assembly sized to receive the filter element.

A filter box assembly for a branched intake system in a vehicle includes an air filter and a filter box housing the air filter. The air filter has a downstream face. The filter box defines an airflow path between a dirty air intake opening and multiple clean air output openings, has a clean air section at the downstream face of the air filter from which each of the clean air output openings open, and includes an interior wall in the clean air section that branches the airflow path to each of the clean air output openings at the downstream face of the air filter.

An exemplary air filter may include an air-permeable filter body for cleaning air, and a filter housing for holding the filter body. The air filter may also include a clean-air port fluidically connected to the filter body and mechanically connected to the filter housing for attaching the air filter to a clean-air channel. The air filter may further include a first air-flow grid arranged in the clean-air port to stabilize the filtered air.

An engine includes an air filter assembly having a filter element and a case. A base of the case includes multiple clips, multiple pins, and a catch. The clips are configured to engage a bottom wall of the filter element. A cover of the case includes multiple hinge wings, a hook, and a guide structure. Each of the hinge wings is coupled with a corresponding pin of the base to allow the cover to rotate about the pins. The hook is configured to fasten to the catch of the base for securing the case in a closed configuration. The guide is configured to facilitate placement of the hook and prevent lateral slipping of the hook from the catch of the base. The base and the cover define an interior volume of the air filter assembly sized to receive the filter element.

An engine includes a breather conduit, an intake conduit, and an air filter assembly. The assembly includes a filter element having a top wall, a bottom wall, a first aperture through the bottom wall, a second aperture through the bottom wall, and filter media extending between the top and bottom walls, wherein the first and second apertures are the same shape, the same size, and are equally spaced apart from the center of the bottom wall. The filter assembly also includes a case. The filter element is configured to be received in the case such that the breather conduit and the intake conduit are directed to and from the interior chamber of the filter element, respectively, whereby air filtered by the filter media mixes with unfiltered gases from the breather conduit in the interior chamber of the filter element prior to entering the intake conduit.

A fluid conducting system for transport of a fluid has a housing with an inlet for the fluid and an outlet for the fluid. A sensor is arranged in the housing or protrudes from an exterior into the housing and measures a mass flow or a volume flow of a fluid flow that is flowing through the housing from the inlet to the outlet. A filter element is arranged upstream of the sensor in the housing. A fluid channel section has an inlet cross section and an outlet cross section, wherein the fluid channel section is arranged upstream of and in front of the sensor and the outlet cross section adjoins the sensor. The fluid channel section has a tapering cross section tapering from the inlet cross section toward the sensor and accelerating at least a portion of the fluid flow and conducting the fluid flow to the sensor. The tapering cross section of the fluid channel section tapers constantly at least in an area of the outlet cross section in front of the sensor.

A filter box assembly for a branched intake system in a vehicle includes an air filter and a filter box housing the air filter. The air filter has a downstream face. The filter box defines an airflow path between a dirty air intake opening and multiple clean air output openings, has a clean air section at the downstream face of the air filter from which each of the clean air output openings open, and includes an upright wall in the clean air section that branches the airflow path to each of the clean air output openings at the downstream face of the air filter.