An off-road vehicle includes a frame and an engine. The engine includes a cylinder block and a cylinder head, on which an exhaust passage is arranged. The cylinder head is provided with a supplementary air supply passage for mixing air into the exhaust gas discharged from the combustion chamber. Alternatively, the supplementary air supply passage can be included in the exhaust system, such as in a cylinder head mounting flange of the exhaust pipe, upstream of an oxygen sensor and first and second stage catalytic converters. The exhaust gas from the engine is further oxidized by air, which reduces the content of components such as CO and NOx in the exhaust gas, improving environmental protection.

A latching mechanism removably attaches an accessory to an offroad vehicle without requiring tools. The latching mechanism includes a body, a shaft extending through the body, and a handle riding on a conical surface of the body for rotating the shaft relative to the body. An oblong head extends on a lower side of the body, rotatable by the handle and shaft to a position where the head extends under a shoulder of a mounting recess. A spring system biases the head axially, such that the head can be moved either upwardly or downwardly from a balanced elevation set by a nut tightenable on a bolt. The mounting recess has an upper portion shaped differently from a lower portion. The body includes a hooking portion which extends significantly above the top of the mounting recess.

A vehicle includes a first suspension between a body and a front wheel, and a second suspension between the body and a rear wheel. An angle θ1 represents a ramp brake-over angle, and angles θ2, θ3, and θ4 respectively represent angles corresponding to the ramp brake-over angle when the first and the second suspension are fully stretched, fully compressed and fully stretched respectively, and fully stretched and fully compressed respectively. When a wheelbase is not smaller than about 1340 mm, the angle θ1 is not smaller than about 55 degrees, a value θ2/θ1 is not smaller than about 1.25, a value θ3/θ1 is not smaller than about 0.9, and a value θ4/θ1 is not smaller than about 0.8. When the wheelbase is not smaller than about 1340 mm and not greater than about 2000 mm, a wheel travel on the rear wheel side is not smaller than about 360 mm, a ratio of a stretch-side value to a compression-side value (stretch-side/compression-side) of the wheel travel on the rear wheel side is not smaller than about 0.5, and a value θ2/θ1 is not smaller than about 1.25.

A vehicle includes a first suspension between a body and a front wheel, and a second suspension between the body and a rear wheel. An angle θ1 represents a ramp brake-over angle, and angles θ2, θ3, and θ4 respectively represent angles corresponding to the ramp brake-over angle when the first and the second suspension are fully stretched, fully compressed and fully stretched respectively, and fully stretched and fully compressed respectively. When a wheelbase is not smaller than about 1340 mm, the angle θ1 is not smaller than about 55 degrees, a value θ2/θ1 is not smaller than about 1.25, a value θ3/θ1 is not smaller than about 0.9, and a value θ4/θ1 is not smaller than about 0.8. When the wheelbase is not smaller than about 1340 mm and not greater than about 2000 mm, a wheel travel on the rear wheel side is not smaller than about 360 mm, a ratio of a stretch-side value to a compression-side value (stretch-side/compression-side) of the wheel travel on the rear wheel side is not smaller than about 0.5, and a value θ2/θ1 is not smaller than about 1.25.

A straddled vehicle includes a footrest including a center step and a rear step. When a perpendicular bisector of a first line segment connecting a front end and a rear end of the rear step is defined as an imaginary first reference line, a center of gravity of the straddled vehicle is ahead of the first reference line and the grounding point of the rear wheel is behind the first reference line when the first line segment is horizontal. When a second line segment connects a front end and a rear end of the center step, and a straight line perpendicular to the second line segment and extending through the rear end of the first step is defined as an imaginary second reference line, the center of gravity of the straddled vehicle is behind the second reference line within a range of about 100 mm or is ahead of the second reference line.

A drive package includes a remote located CVT and a motor where the CVT is positioned rearward (or forward) of the motor. An auxiliary drive mechanism couples a drive shaft of the CVT to a crankshaft of the motor. The auxiliary drive mechanism is a belt or chain. The drive shaft is substantially parallel to, and longitudinally offset from, the crankshaft. Thus, the width of the drive package is reduced as compared to ATVs having a CVT located adjacent the motor.

A drive package includes a remote located CVT and a motor where the CVT is positioned rearward (or forward) of the motor. An auxiliary drive mechanism couples a drive shaft of the CVT to a crankshaft of the motor. The auxiliary drive mechanism is a belt or chain. The drive shaft is substantially parallel to, and longitudinally offset from, the crankshaft. Thus, the width of the drive package is reduced as compared to ATVs having a CVT located adjacent the motor.

An oil cooling assembly for an All-Terrain Vehicle (ATV) and a method of improving the efficiency of the ATV's cooling system is provided. The assembly or kit may include a relocating bracket that can be used to affix the original equipment manufacturer (OEM) oil cooler to a front portion of the ATV after the OEM oil cooler is removed from underneath the ATV frame. The kit may include a new reservoir tank that is larger than the OEM oil tank, as the relocation of the OEM oil cooler affords more spaced to accommodate the larger reservoir tank. The kit includes fluid conduits and barbed fittings to fluidly connect the relocated oil cooler to the reservoir tank, the reservoir tank to the motor, and the motor to the relocated oil cooler.

An oil cooling assembly for an All-Terrain Vehicle (ATV) and a method of improving the efficiency of the ATV's cooling system is provided. The assembly or kit may include a relocating bracket that can be used to affix the original equipment manufacturer (OEM) oil cooler to a front portion of the ATV after the OEM oil cooler is removed from underneath the ATV frame. The kit may include a new reservoir tank that is larger than the OEM oil tank, as the relocation of the OEM oil cooler affords more spaced to accommodate the larger reservoir tank. The kit includes fluid conduits and barbed fittings to fluidly connect the relocated oil cooler to the reservoir tank, the reservoir tank to the motor, and the motor to the relocated oil cooler.

A modular cargo system for an off-road vehicle includes a triangular center case between a right side case and a left side case, each having a base attached downwardly to a platform on the vehicle while also defining a floor plane for resting on a flat floor surface. The side cases include non-parallel side walls, each defining an interior space large enough to hold a rider's helmet. Each case includes a handle on a hinged lid, enabling the side case to be carried with a single hand while the lid is closed. The hinge is on a leading side wall of the cases, latched on a trailing side wall of the cases, and clips to hold the side cases downward to the platform are on the trailing side walls.