Abstract: A watercraft includes a shell, a ride plate, an internal combustion engine, and a jet pump. The shell defines a tunnel that extends forwardly from the transom and is defined laterally by the shell. The tunnel is open at its bottom The ride plate mounts to the shell under the tunnel. The engine and jet pump are supported by the ride plate and disposed in the tunnel. The engine drives the jet pump. The engine is cooled by water that continuously flows past the ride plate. The engine, jet pump, and ride plate are installed from below or the behind the shell.

Abstract: A propulsion assembly for propelling an aircraft is disclosed. The assembly includes a four stroke internal combustion engine, a propeller shaft that is operatively connected to the engine, and an electronic control unit that is connected to the engine and is configured to monitor and control at least one operating parameter of the engine. The engine includes two to twelve cylinders having a total displacement of less than 19.6 liters, and a crankshaft that is operatively connected to the cylinders. The crankshaft rotates at a speed of at least 3,000 rpm when the engine is operating under normal conditions. The engine also includes a closed loop liquid cooling system and a fuel injection system. The engine has a total power output of 140 to 600 hp, and a total wet installed weight of less than 1.1 kg/hp. The engine meets current RTCA DO-160d, RTCA DO-178b, and US FAA FAR33 guidelines.

Abstract: A personal watercraft is disclosed with a hull, a seating assembly, and a four stroke internal combustion engine below the seating assembly. The engine has at least one intake valve for each of the combustion cylinder chambers, at least one exhaust valve for each of the combustion cylinder chambers, and a valve actuation assembly located in a cylinder head for operating the intake and exhaust valves. At least one air intake passageway is operatively coupled to the combustion cylinder chambers through the intake valves. An air intake manifold is connected to the cylinder head and operatively connected to the at least one air intake passageway. The engine also has a supercharger for boosting air to the air intake manifold. The watercraft also includes a propulsion unit, operatively coupled to the crankshaft, which is located on one end of the two ends of the crankcase.

Abstract: A pop-off valve that, in one embodiment, provides overboost protection for an aircraft engine, is described. The pop-off valve includes a housing adapted for connection to a portion of a drive device containing a pressure medium. It also includes a pressure body movably disposed in the housing such that, in operation, a first side of the pressure body is exposed to the pressure medium while a second side is exposed to a reference force. In addition, the pop-off valve incorporates a control device adapted to receive at least one signal concerning at least one operating parameter of the drive device and, in response to the operating parameter signal, to control the reference force. As a result of movement of the pressure body within the housing, at least one first opening in the housing is exposed, permitting venting of the pressure medium.

Abstract: A combined flame arrester and intercooler for cooling intake gas for an internal combustion engine is disclosed. The intercooler comprises an elongated body having a longitudinal axis. The elongated body has a central passageway that extends substantially parallel to the longitudinal axis. An inlet opening is located on one end of the elongated body such that the intake gas enters the central passageway though the inlet opening. The intercooler further includes a plurality of cooling tubes forming at least a portion of the elongated body. The plurality of tubes substantially surround the central passageway. Each of the cooling tubes is spaced from an adjacent cooling tube such that an air flow path is formed there between. The intake gas is cooled by flowing past the cooling tubes. Preferably, the intake gas flows along the central passageway in the elongated body and radially outward therefrom through the air flow path between the cooling tubes.

Abstract: A watercraft includes a shell, a ride plate, an internal combustion engine, and a jet pump. The shell defines a tunnel that extends forwardly from the transom and is defined laterally by the shell. The tunnel is open at its bottom The ride plate mounts to the shell under the tunnel. The engine and jet pump are supported by the ride plate and disposed in the tunnel. The engine drives the jet pump. The engine is cooled by water that continuously flows past the ride plate. The engine, jet pump, and ride plate are installed from below or the behind the shell.

Abstract: An internal combustion engine includes a crankcase, a cylinder, a piston, a crankshaft, and a piston connecting rod. A counterweight connects to the crankshaft through a counterweight connecting rod. The counterweight pivotally connects to the crankcase. The engine is constructed such that the crankshaft drives the counterweight less than 180 degrees out of phase with the motion of the piston. A center of gravity of the crankshaft is offset from the crankshaft's axis and moves out of phase with the piston by less than 180 degrees. The offset counterweight and crankshaft balance out inertial forces in the engine to reduce engine vibrations and improve engine performance.

Abstract: A power unit is described that combines an internal combustion engine and a lubrication system. The internal combustion engine includes a crankcase suction chamber and a transmission case suction chamber. At least one partition separates the crankcase suction chamber from the transmission case suction chamber. The lubrication system supplies lubricant to the internal combustion engine. The lubrication system includes a lubrication tank and a supply line for supplying lubricant to the internal combustion engine. At least one crankcase drainage line extends from the crankcase to drain a fluid from the crankcase suction chamber and transfer the fluid to the transmission case suction chamber. At least one pump operatively connects to one of either the crankcase chamber or the transmission case chamber. By the operation of the at least one pump, a negative pressure within at least one of the crankcase chamber and the transmission case chamber is created.

Abstract: A modular family of internal combustion engines is described. The family includes at least three engine configurations selected from a single cylinder, V-type, inline, opposed, W-type, and radial configurations. Each of the engines in the family includes at least one cylinder with identical top end packages. A method for designing such a family of engines is also disclosed. A family of recreational vehicles and method for designing a family of recreational vehicles is also disclosed.

Abstract: A go-kart drive assembly with an internal combustion engine in the form of a reciprocating-piston or rotary-piston engine as a power source is described. The drive assembly includes a spur-gear reduction gearing between the internal combustion engine and a rear-wheel drive shaft of the go-kart. The spur-gear reduction gearing and the crank shaft (17) of the reciprocating engine or the engine shaft of the rotary-piston engine (17a) are accommodated in a common housing (10) that is preferably closed. The space or spaces (a, b) between the shafts of the spur-gear reduction gearing (27, 29; 30, 33) is fixed in the housing (10) so as to be invariable. The driving gear wheel (27) of the gearing (26) is mounted on the crank shaft (17) or the engine shaft (17a) and the driven gear wheel (33) of the gearing (26) is mounted on the rear-wheel drive shaft (6).

Abstract: An all-terrain vehicle (ATV) has a subtransmission detachably fastened to an engine casing. The engine crankshaft includes a drive pulley connected via a belt to a driven pulley in the subtransmission, thus providing a continuously variable transmission (CVT) between the engine crankshaft and the subtransmission. The subtransmission includes a 2WD-4WD selector mechanism to select two-wheel-drive or four-wheel-drive and also includes a transmission selector mechanism to put the vehicle in park, neutral, reverse, high-speed drive or low-speed drive. By disposing these selector mechanisms in the subtransmission, mass centralization is improved relative to prior-art drivetrains wherein the 2WD-4WD selector mechanism connects to the front differential. When operating in 2WD mode, the drivetrain does not waste energy rotating the front drive shaft, as in the prior art.

Abstract: A power unit is described that combines an internal combustion engine and a lubrication system. The internal combustion engine includes a crankcase suction chamber and a transmission case suction chamber. At least one partition separates the crankcase suction chamber from the transmission case suction chamber. The lubrication system supplies lubricant to the internal combustion engine. The lubrication system includes a lubrication tank and a supply line for supplying lubricant to the internal combustion engine. At least one crankcase drainage line extends from the crankcase to drain a fluid from the crankcase suction chamber and transfer the fluid to the transmission case suction chamber. At least one pump operatively connects to one of either the crankcase chamber or the transmission case chamber. By the operation of the at least one pump, a negative pressure within at least one of the crankcase chamber and the transmission case chamber is created.

Abstract: An aircraft control system includes a propeller governor in which a stepper motor is used to apply a compression force on a speeder spring, and a turbocharger in which a stepper motor is used to actuate a needle valve associated with a diaphragm cell. An electronic control unit may be used to control the stepper motor in the propeller governor and the stepper motor in the turbocharger. The integration of the propeller governor and the turbocharger into a single control system decreases the number of individual adjustments that must be performed manually by the pilot.

Abstract: An arrangement of a four cycle engine is disclosed for use in a vehicle providing a relatively low center of gravity for improved handling and maneuverability. The engine components are located on opposing sides of the longitudinal axis of the vehicle and behind the axis of the crankshaft to move the center of gravity to the middle of the vehicle.

Abstract: An exhaust valve assembly for a two stroke internal combustion engine having a cylinder with at least one main exhaust port and one auxiliary exhaust port is disclosed. The assembly comprises a main exhaust valve for at least partially closing the main exhaust port, an auxiliary exhaust valve for at least partially closing the auxiliary exhaust port, the auxiliary exhaust valve being separate from the main exhaust valve, and an actuator for actuation of the main exhaust valve and the auxiliary exhaust valve, wherein the actuator is connected to the main exhaust valve and the auxiliary exhaust valve is connected to the actuator by the main exhaust valve.

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: An all terrain vehicle (“ATV”) is disclosed having a frame with front, rear, right, and left sides. An engine and at least two wheel axes are disposed on the frame. A plurality of wheels are disposed on the at least two wheel axes. The engine includes a cylinder disposed adjacent a crankshaft and a generator operatively connected to the crankshaft. An output shaft, separate from the crankshaft, operatively connects to the engine to transmit power from the engine to at least one of the plurality of wheels through at least one of the wheel axes. The output shaft is disposed between the cylinder and the generator in a plane substantially perpendicular to at least one of the wheel axes.

Abstract: A decompressor for use in an internal combustion engine is disclosed The decompressor is at least partially located within the venting passageway in response to pressure in the combustion chamber for selectively opening the venting passageway such that combustion gas located within the chamber is vented to the induction passageway. The decompressor opens the venting passageway when the engine is off and during an engine start up operation. The decompressor includes an expansible cavity operatively connected to the combustion chamber.

Abstract: An internal combustion engine for an aircraft is described. The internal combustion engine includes a crankshaft defining first and second ends, a propeller, and a transmission disposed between the first end of the crankshaft and the propeller, operatively connecting the propeller to the crankshaft. A torsion bar is disposed between the first end of the crankshaft and the transmission, operatively connecting the crankshaft to the transmission. A torsional vibration damper is operatively connected at one of the first and the second ends of the crankshaft.

Abstract: A dry sump lubrication system for a four cycle engine is disclosed. The dry sump lubrication system has at least two lubricant storage chambers. A first lubricant storage chamber stores a first volume of lubricant. The first lubricant storage chamber may be located in a lower part of the crankcase. A second lubricant storage chamber is an oil tank and stores a second volume of lubricant. The oil tank may be secured to the output end of the crankcase. The first lubricant storage chamber is capable of storing at least 30% of a total volume of lubricant within the dry sump lubrication system.