Abstract: A two-cycle internal combustion engine has an ignition timing that varies with engine speed. A plurality of ignition patterns (the relationship between ignition timing and engine speed) are used. The engine exhaust gas temperature is sensed and is used to determine the particular ignition pattern used at a particular time.

Abstract: A two-cycle internal combustion engine has an ignition timing that varies with engine speed. A plurality of ignition patterns (the relationship between ignition timing and engine speed) are used. The engine exhaust gas temperature is sensed and is used to determine the particular ignition pattern used at a particular time.

Abstract: A watercraft of the jet propulsion type comprising a steering mechanism, a throttle control mechanism, a thrust mechanism, a throttle regulator and a controlled thrust steering system. The steering mechanism has a straight-ahead position. The steering mechanism is able to rotate in a clockwise direction from the straight-ahead position to a clockwise position and in a counter-clockwise direction from the straight-ahead position to a counter-clockwise position. The throttle control mechanism is biased toward an idle position. The thrust mechanism provides jet propulsion thrust for the watercraft. The throttle regulator regulates thrust provided by the thrust mechanism. The controlled thrust steering system causes the throttle regulator to increase thrust upon the steering mechanism rotating from the straight-ahead position to the clockwise position or the counter-clockwise position.

Abstract: An internal combustion engine has a variable flow passage, e.g. an exhaust passage, in communication with the cylinder of the engine. A valve is positioned in the passage, restricting the passage to reduce the flow therethrough. A control mechanism varies the position of the valve by making use of positive and negative pressure, which can be supplied from the engine crankcase or an independent source. The control of positive or negative pressure supply can be based on engine speed, engine load or throttle position. The control mechanism can include a diaphragm located in a pressure chamber to which the positive and negative pressure is supplied.

Abstract: A watercraft of the jet propulsion type comprising a steering mechanism, a throttle control mechanism, a thrust mechanism, a throttle regulator and a controlled thrust steering system. The steering mechanism has a straight-ahead position. The steering mechanism is able to rotate in a clockwise direction from the straight-ahead position and in a counter-clockwise direction from the straight-ahead position. The throttle control mechanism is biased toward an idle position. The thrust mechanism provides jet propulsion thrust for the watercraft. The throttle regulator regulates thrust provided by the thrust mechanism. The controlled thrust steering system causes the throttle regulator to increase thrust upon the steering mechanism rotating from the straight-ahead position.

Abstract: An edge trim piece for sealing the junction between top and bottom hull members of a watercraft includes a main body having a first end for engaging the top hull member, a second end for engaging the bottom hull member and a bridging section between the first and second ends for overlying the junction between the hull members. The edge trim piece has a sealing cover for the bridging section that has a first end secured to the first end of the main body and a second end that extends in the direction of but is not secured to the second end of the main body.

Abstract: An adjustable shock absorber having a movable sealing piston located within the shock absorber for sealing fluid and a suspension adjuster connected to the shock absorber for moving fluid between the adjuster and the shock absorber so as to change the overall length of the shock absorber without changing the stroke length.