Abstract: A motorcycle powered by a two cycle crankcase compression fuel injected internal combustion engine. The injection system for the engine includes a main fuel air/injector that injects fuel directly into the combustion chamber and a second or auxiliary fuel injector that injects fuel into the induction system for the engine. Control means control the fuel injectors so that the second or auxiliary fuel injector supplies fuel only during starting and high load, high speed conditions. The engine components are laid out in such a way that the spark plugs of the engine and the fuel injector will each be exposed to unobstructed air flow for cooling.

Abstract: A fuel injection system for an internal combustion engine having a fuel pump drive for driving a fuel pump of the injection system at different speed ratios depending upon the engine conditions. The pump is driven at a higher speed during starting than when the engine is operating.

Abstract: A motorcycle powered by a two cycle crankcase compression fuel injected internal combustion engine. The injection system for the engine includes a main fuel air/injector that injects fuel directly into the combustion chamber and a second or auxiliary fuel injector that injects fuel into the induction system for the engine. Control means control the fuel injectors so that the second or auxiliary fuel injector supplies fuel only during starting and high load, high speed conditions. The engine components are laid out in such a way that the spark plugs of the engine and the fuel injector will each be exposed to unobstructed air flow for cooling.

Abstract: A number of embodiments of mounting arrangements for the pressure sensor of a control for the fuel injection system of a two cycle crankcase compression internal combustion engine. The pressure sensor is mounted in such a way as to avoid the likelihood of the pressure signal being deteriorated due to fuel and lubricant accumulation and deterioration thereon. In some embodiments, this is done by an insulated mouting and in others this is done by positioning the pressure sensor in a scavenge passage to the engine. In the scavenge passage mounting arrangements, insulation is also employed.