An air intake structure for an engine provided with an air cleaner near an exhaust muffler includes: a case defining an air intake chamber; an air cleaner element housed in the case to divide the air intake chamber into a dust chamber and a clean chamber; a first air inlet formed in a part of the case close to the exhaust muffler such that the first air inlet communicates the dust chamber with an exterior of the case; a second air inlet formed in a part of the case distant from the exhaust muffler such that the second air inlet communicates the dust chamber with an exterior of the case; a communication opening formed in the case so as to communicate the clean chamber with an air intake passage; and an opening and closing mechanism for selectively opening and closing at least one of the first and second air inlets.

An air intake system for an internal combustion engine of a vehicle includes a main housing defining an interior chamber configured to receive an air filter, a cover seated on the main housing to enclose the air filter within the interior chamber, dual intake ducts fluidly coupled to the interior chamber and configured to provide cold intake air directly from a high pressure zone behind a vehicle grille, an air outlet formed in the main housing and configured to receive intake air that has passed through the air filter, and an air intake duct having a first end coupled to the air outlet and a second end configured to couple to a throttle body of the engine. The air intake system is configured to provide a short airflow path directly into the engine rather than through a tortuous path.

An air cleaner includes an air cleaner case, an element disposed in the air cleaner case, and an intake port disposed in the air cleaner case. With respect to an imaginary plane extending in opposite first and second directions, opposite third and fourth directions, and opposite fifth and sixth directions that are perpendicular to each other, the air cleaner case includes a first half located at a side of the fifth direction and a second half located at a side of the sixth direction, with respect to an imaginary plane in which the first to fourth directions extend. The intake port is formed in the first half of the air cleaner case. The air cleaner case includes a closed wall at a position substantially symmetric to a position of the intake port with respect to the imaginary plane.

The present invention relates to an autonomous agricultural machine comprising a frame having an inverted U-section, the autonomous agricultural machine having a roof and comprising a thermal engine system comprising an engine, the autonomous agricultural machine comprising a cooling system having an air circulation duct arranged in the upper part of the frame, directly under the roof, the duct having at least one opening to allow the intake of outside air into the air circulation duct and an upper air outlet to expel the hot air upwards, to the top of the roof, the cooling system also comprising a ventilation device to ensure air circulation in the air circulation duct, the air circulation duct being configured to allow the circulation of fresh air to cool the engine.

A two-wheeled vehicle may include a frame, a plurality of ground-engaging members for supporting the frame and an engine supported by the frame and operably coupled to the ground-engaging members. Additionally, the two-wheeled vehicle may include an airbox including inlet tube and a filter. The airbox may include by a first housing portion, a second housing portion, and a vertical seam coupling the first and second housing portions.

An off-road vehicle includes an intake box, an introduction duct, and an intake duct. The intake box includes an internal space, an opening, and a bottom wall. The opening is provided with a filter, and the internal space is open to an outside of the off-road vehicle through the opening. The bottom wall defines a lower boundary of a part of the internal space. Through the introduction duct, the internal space of the intake box communicates with an outside of the intake box. The introduction duct protrudes upward and toward the internal space from the bottom wall of the intake box. The introduction duct includes an inlet provided at a position higher than the bottom wall in the internal space of the intake box. The intake duct is provided at the outside of the intake box and connected to the introduction duct.