Abstract: An all terrain vehicle (“ATV”) is disclosed having a frame with front, rear, right, and left sides. The frame defines a frame centerline extending longitudinally between the front and the rear sides. The ATV includes an engine with at least one cylinder having an axis that defines an engine centerline. The all terrain vehicle also includes an output shaft defining an output shaft centerline. A continuously variable transmission (“CVT”) operatively connects the engine to the output shaft and defines a CVT centerline. The engine centerline, output shaft centerline, and CVT centerline are positioned with respect to one another and the frame centerline. In one embodiment, the engine centerline is disposed between the output shaft centerline and the CVT centerline. In this embodiment, the engine centerline also may lie between the frame centerline and the CVT centerline.

Abstract: Disclosed is an all terrain vehicle with an improved engine and power train. The engine is located under the seat and the hingably seat provides for ready access to the engine for maintenance and repair. The engine is placed in the vehicle such that the crankshaft is parallel to the line of travel; that is to say that the crankshaft is in line with the longitudinal axis of the vehicle. The engine has a split output shaft; that is to say, two output shafts. One shaft extends forwardly of the engine to a front transmission on the front axle and the second extends rearwardly to a rear transmission on the rear axle. The output shafts run directly to the transmissions in a straight line. The front and rear output shafts are connected by gears which enables different ratios of revolution between the front and rear axle if necessary. The all terrain vehicle is also equipped with a unique parking gear which essentially locks the two output shafts to the transmission housing.

Abstract: A four stroke internal combustion engine is disclosed having a power take off housing located at one end of the engine. A crankshaft is operatively connected to a drive shaft and the cam shaft within the power take off housing. Furthermore, the crankshaft is operatively coupled within the power take off housing to at least one of a generator, an engine starting mechanism, a balance shaft, and a supercharger.

Abstract: A control tensioner device for adjusting and maintaining the tension in a flexible linkage in an engine includes a retainer having a central passageway extending therethrough. At least a portion of the central passageway contains a first set of threads. The control tensioner device further includes an adjustment element having a second set of threads. The adjustment element is sized to be threadably received within the central passageway. The adjustment element is adapted to apply pressure on the flexible linkage to maintain the tension. The first set of threads and second set of threads are sized to permit minor relative movement between the retainer and the adjustment element. Furthermore, the first set of threads and second set of threads are sized to be borderline self-locking such that the first and second sets of threads engage in response to minor relative movement between the retainer and the adjustment element.

Abstract: A transmission system for a straddle vehicle which provides two operating modes, namely semi-automatic and automatic. With the semi-automatic transmission system, an operator only uses a switching means mounted on a sheeting bar of the vehicle for activating a clutch actuator and a shift actuator. The clutch actuator disengages a transmission clutch while the shift actuator operates a shifter for changing the transmission ratio. With the automatic transmission system, an Electronic Control Unit reads inputs signals such as speed of the engine (RPM), speed of the vehicle, opening of a throttle valve and position of a shifter and accomplishes a smooth shifting by activating a clutch actuator, a shift actuator and a modulated controlling valve.

Abstract: An all terrain vehicle comprises an engine located under a hingably mounted seat, the seat providing ready access to the engine for maintenance and repair. The engine is placed in the vehicle such that the crankshaft is parallel to the line of travel and the crankshaft is in line with the longitudinal axis of the vehicle. The engine has two output shafts. The front output shaft extends forwardly of the engine to a front differential on the front axle and the rear output shaft extends rearwardly to a rear differential on the rear axle. The front and rear output shafts are in communication with one another by gears which enables different ratios of revolution between-the front and rear axle. The all terrain vehicle is also equipped with a parking gear which locks the two output shafts and prevents rotation with respect to the transmission housing.

Abstract: A transmission system for a straddle vehicle which provides two operating modes, namely semi-automatic and automatic. With the semi-automatic transmission system, an operator only uses a switching means mounted on a steering bar of the vehicle for activating a clutch actuator and a shift actuator. The clutch actuator disengages a transmission clutch while the shift actuator operates a shifter for changing the transmission ratio. With the automatic transmission system, an Electronic Control Unit reads inputs signals such as speed of the engine (RPM), speed of the vehicle, opening of a throttle valve and position of a shifter and accomplishes a smooth shifting by activating a clutch actuator, a shift actuator and a modulated controlling valve.

Abstract: In an internal-combustion engine comprising at least one cylinder having a port and a piston which is reciprocable to open and close said port, the effective axial extent of said port is adapted to be reduced by a restricting member, which is movably mounted adjacent to a flow passage which adjoins said port. The restricting member has a restricting edge and is movable to a restricting position in which said restricting edge is substantially flush with the peripheral surface of the cylinder bore. The restricting member defines the exhaust passage on one side thereof adjacent to the exhaust port. In order to improve the cooling of the cylinder and the exhaust gas flow, the restricting member constitutes a hinged member, which is pivoted on an axis at that end which is opposite to the restricting edge.