Abstract: An air-cooled engine is hung and fixed under a rear part of a backbone of a body frame. The engine is disposed so that the center axis of a cylinder in its cylinder block extends approximately horizontally and so that its cylinder head is directed toward the front. A fuel injection device is located between an intake valve and an intake port in the cylinder head. An injection nozzle of the fuel injection device and an intake valve opening are placed at a short distance. While the vehicle is idling or running at low speed, the vicinity of the tip of an injector of the fuel injection device is cooled by assist air supplied from a throttle body through a secondary passage, and when the vehicle runs normally or at high speed, the fuel injection device is cooled by the wind that hits the cylinder head.

Abstract: An air-cooled engine is hung and fixed under a rear part of a backbone of a body frame. The engine is disposed so that the center axis of a cylinder in its cylinder block extends approximately horizontally and so that its cylinder head is directed toward the front. A fuel injection device is located between an intake valve and an intake port in the cylinder head. An injection nozzle of the fuel injection device and an intake valve opening are placed at a short distance. While the vehicle is idling or running at low speed, the vicinity of the tip of an injector of the fuel injection device is cooled by assist air supplied from a throttle body through a secondary passage, and when the vehicle runs normally or at high speed, the fuel injection device is cooled by the wind that hits the cylinder head.

Abstract: Several embodiments of direct injected spark ignited internal combustion engines. In these embodiments, the fuel injector is positioned quite close to the cylinder bore axis so as to ensure a homogeneous mixture in the combustion chamber under all running conditions and particularly high speed high load conditions. The injector in each embodiment is positioned, however, relative to this spark plug or plugs so that fuel will not be sprayed into their gap to cause fouling. In addition, an improved arrangement for showing heat transfer from both the spark plugs and fuel injectors to the engine coolant is also disclosed.

Abstract: A number of embodiments of induction systems for multiple valve internal combustion engines wherein the performance of the engine is improved throughout the engine speed and load ranges by providing variable effective areas for the induction passages. The embodiments disclosed all relate to three intake valve engines and show a number of different variations in intake passages. In all embodiments an EGR system is employed for improving exhaust emission control.

Abstract: A number of embodiments of induction systems for multiple valve internal combustion engines wherein the performance of the engine is improved throughout the engine speed and load ranges by providing variable effective areas for the induction passages. The embodiments disclosed all relate to three intake valve engines and show a number of different variations in intake passages. In all embodiments an EGR system is employed for improving exhaust emission control.

Abstract: A number of embodiments of twin overhead cam shaft reciprocating machines having a plurality of poppet valves. A variable valve timing mechanism is interposed between the cam shafts and respective of the poppet valves for varying their lift and for changing the number of effective poppet valves per cylinder. The lift changing mechanism includes means for shifting at least one rocker arm follower and provides a relatively compact yet highly efficient structure for achieving this purpose.

Abstract: A number of embodiments of multi-valve internal combustion engines having a manifold fuel injection and a control valve which changes the air flow pattern into the combustion chamber between an unrestricted flow and a restricted flow wherein turbulence is generated. An air assist arrangement including a number of different embodiments of insert pieces are employed for changing the spray pattern in response to the position of the control valve so as to provide the desired fuel flow into the combustion chamber when the control valve is controlling the air flow.

Abstract: A number of embodiments of twin overhead cam shaft reciprocating machines having a plurality of poppet valves. A variable valve timing mechanism is interposed between the cam shafts and respective of the poppet valves for varying their lift and for changing the number of effective poppet valves per cylinder. The lift changing mechanism includes means for shifting at least one rocker arm follower and provides a relatively compact yet highly efficient structure for achieving this purpose.

Abstract: Two embodiments of multiple-valve engines wherein both the spark plug and fuel injector are mounted in the cylinder head in side-by-side relationship with their axes lying in a common plane. The spark plug and fuel injector axes extend into the combustion chamber recess in an area that is circumscribed by a circle passing through the centers of the valve seats.

Abstract: A number of embodiments of twin overhead cam shaft reciprocating machines having a plurality of poppet valves. A variable valve timing mechanism is interposed between the cam shafts and respective of the poppet valves for varying their lift and for changing the number of effective poppet valves per cylinder. The lift changing mechanism includes means for shifting at least one rocker arm follower and provides a relatively compact yet highly efficient structure for achieving this purpose.

Abstract: A number of embodiments of multiple-valve internal combustion engines having at least some of the valves being deactivatable by means of a hydraulic tappet assembly so as to control the flow path and flow pattern into and out of the combustion chamber. A hydraulic system is provided for controlling which of the valves operate and, if desired, the lift of the valves.

Abstract: A number of embodiments of overhead cam internal combustion engines having multiple intake and exhaust valves. The valve actuating mechanism is such that the valves are opened at a non-symmetrical rate so as to minimize the clearance requirements at top dead center and also so as to minimize the overlap between the closing of the exhaust valve and the opening of the intake valve without decreasing volumetric efficiency. A number of embodiments having either direct or rocker arm actuation are disclosed.

Abstract: A number of embodiments of multiple intake valve internal combustion engines that permit the generation of tumble in one direction and at a high velocity under one engine running condition and counter tumble at a lower velocity but in a higher flow volume under other running conditions. The system includes an arrangement for disabling the operation of at least one of the intake passages and for redirecting the flow through another of the intake passages. Embodiments having two, three, and four intake valves per cylinder are disclosed.

Abstract: An induction system and combustion chamber configuration for a multiple valve internal combustion engine wherein a tumble action is generated in the combustion chamber about an axis that extends transversely relative to the axis of the cylinder bore and which tumble axis is disposed so as to be substantially at the center of the combustion chamber volume when the piston is at its maximum speed during the compression stroke. This is accomplished by changing the lift, effective flow areas, and/or size of the intake passages.