Abstract: An air intake noise reduction apparatus is provided which can effectively reduce air intake noise even with simple construction requiring a small number of components. Four air intake passages 24, 25, 26, 27 which each have different passage lengths are formed by connecting an upper wall 17 and a lower wall 18 of an air intake noise reduction duct 11 which are flattened in a vertical direction with three partition walls 21, 22, 23. Air intake noise can be reduced by making pulsating air interfere with one another which is generated in the plurality of air intake passages 24, 25, 26, 27 which each have the different passage lengths in such a manner as to have different phases shifted from one another. In addition, since the partition walls function as a reinforcement rib, the rigidity of the air intake noise reduction duct 11 can be enhanced.

Abstract: A motor vehicle intake muffler duct is formed by integrally bonding an upper duct, a lower duct and a separator interposed between them. Three airways are formed between the upper duct and the separator, seven muffler chambers are formed between the lower duct and the separator, and the airways and the muffler chambers are communicated with each other through vent holes which are formed in the separator. An intake muffler duct in which multiple muffler chambers are integrated with the airways, can be formed from only three components, which are an upper duct, a lower duct and a separator, and moreover although it has a compact structure, it is possible to reduce the intake noise effectively.

Abstract: A continuously variable hydraulic transmission operatively interconnects a transmission mechanism and a clutch mechanism. The hydraulic transmission includes an oil pump having an inlet port and an outlet port and a transmission ratio control member such as a swash plate which is displaceable for varying the transmission ratio between a higher-speed position, a lower-speed position, and a neutral position, an oil motor having an inlet port and an outlet port and drivable by the oil pump, a first oil passage hydraulically interconnecting the outlet port of the oil pump and the inlet port of the oil motor, a second oil passage hydraulically interconnecting the inlet port of the oil pump and the outlet port of the oil motor, a housing accommodating the oil pump, the oil motor, the first oil passage, and the second oil passage, and an oil passage control unit for selectively bringing the first oil passage into and out of hydraulic communication with the second oil passage.

Abstract: A continuously variable hydraulic transmission operatively interconnects a transmission mechanism and a clutch mechanism. The hydraulic transmission includes an oil pump having an inlet port and an outlet port and a transmission ratio control member such as a swash plate which is displaceable for varying the transmission ratio between a higher-speed position, a lower-speed position, and a neutral position, an oil motor having an inlet port and an outlet port and drivable by the oil pump, a first oil passage hydraulically interconnecting the outlet port of the oil pump and the inlet port of the oil motor, a second oil passage hydraulically interconnecting the inlet port of the oil pump and the outlet port of the oil motor, a housing accommodating the oil pump, the oil motor, the first oil passage, and the second oil passage, and an oil passage control unit for selectively bringing the first oil passage into and out of hydraulic communication with the second oil passage.

Abstract: A two-cycle engine of the crank chamber preloading type of the construction in which a crankcase, a cylinder head and a cylinder are clamped together by a plurality of clamping members penetrating the cylinder includes a suction port formed in a wall of the cylinder, an exhaust port formed on a side of the cylinder opposite the suction port, at least one main scavenging port disposed between the suction port and the exhaust port and directed toward the suction port, and at least one ancillary scavenging port disposed above the suction port and juxtaposed against the exhaust port. At least one ancillary scavenging passage branching from at least one main scavenging passage and communicating with the ancillary scavenging port extends around an opening for one of clamping members on the suction side.

Abstract: An internal combustion engine comprising a crankshaft mounted in a crankcase and connected with a piston through a connecting rod, an accessory drive shaft connected at one end with the crankshaft and support at the same end by the crankcase, a water pump including a rotatable element connected with the other end of the accessory drive shaft and a casing having an outlet port connected with a co-operating passage in the crankcase, said casing being secured to the crankcase at the outlet port portion so as to provide a rigid support for the drive shaft.

Abstract: Air-cooled two stroke internal combustion engine having a cooling air blower driven by the engine and a lubricating oil pump for supplying lubricating oil to the engine, said lubricating oil pump being housed in the hub portion of the blower.