Abstract: An electronically controlled fuel injection system for a snowmobile engine utilizing a battery with the fuel injection system having an electronic control unit connected to the battery for operating the system. The engine has an alternator provided for producing an electrical output in response to rotation of the engine. A control switching means is provided for selectively supplying electrical energy to the battery and the control unit upon detecting electrical current from the alternator so that power is supplied to the electronic control unit whenever the engine is in a starting operation either by a rope pull starter or by activating an electric starter.

Abstract: In a microprocessor-based electronic engine control system or ECU for electronic fuel injection which determines the amount of fuel to be injected on the basis of engine RPM and throttle opening position, modified by factors derived from sensed conditions of the engine and the environment, a single, long pulse width priming fuel pulse is injected upon cranking the engine. The priming fuel pulse is selected as an inverse function of engine temperature and delivered to the throttle bodies within a first period of time after the engine is initially turned over. The engine revolutions are counted until the engine starts. If the engine fails to reach a predetermined RPM for a predetermined time period (indicating that it has been successfully started) within a certain number of revolutions of the crankshaft, then a second priming pulse is delivered. The pulse width of the second pulse is independent of the pulse width of the first priming pulse but is again dependent on the engine temperature.

Abstract: A snowmobile ski comprising a longitudinally extending runner having a bottom surface, a generally flat elongate bar having a top and bottom surface, and a steering skag extending longitudinally of the runner on the bottom side of the bar. The flat bar is generally contoured to abut the bottom surface of the runner, and furthermore extends forwardly beyond the skag and laterally and longitudinally beyond the skag so that a skag track in the snow encountered by the ski and the skag track left by the skag in the snow will be at least partially filled in by the bar.

Abstract: A first fuel injection pulse width is provided based on engine operating conditions. The amount of fuel is necessary for one combustion stroke of the engine at one time. A second fuel injection pulse width is provided based on engine operating conditions so as to inject at one time an amount of fuel for two combustion strokes of the engine. The first fuel injection pulse width is compared with a minimum value. The first fuel injection pulse width is selected when the first fuel injection pulse width is larger than the minimum value, and otherwise, the second fuel injection pulse width is selected when the first fuel injection pulse width is smaller than the minimum value. Fuel is injected at the selected injection pulse.

Abstract: The internal combustion engine has a battery and a magneto for an ignition system of the engine. The magneto has a charge coil and a source coil for generating a first alternating current and a second alternating current, respectively. The alternating current is rectified and the rectified current is supplied to the battery for charging. The second alternating current is supplied to electric loads to be operated by the engine.

Abstract: An ignition device intermittently produces an ignition voltage in synchronism with speed of an engine. A fuel injection control is provided for operating a fuel injector for injecting fuel. A fuel pump for supplying fuel to the fuel injector is stopped at a time after the ignition and fuel injection stop, thereby keeping fuel pressure in a fuel supply passage.

Abstract: A crankcase temperature sensor is provided for detecting temperature of a crankcase. A low speed basic injection pulse width is provided based on the detected crankcase temperature for low engine speed. An ordinary fuel injection pulse width is provided in accordance with engine operating conditions for ordinary engine operating condition. A comparator is provided for comparing the low speed injection pulse width and the ordinary fuel injection pulse width with each other. A larger injection pulse width is determined for injecting fuel.

Abstract: A motor vehicle has a continuously variable belt-drive transmission having a clutch means which engages when speed of an engine is higher than a clutch engaging speed. A plurality of basic pulse widths for injecting fuel are stored in a memory arranged in accordance with the engine speed and opening degree of a throttle valve. Some of the basic pulse widths in a speed range lower than the clutch engaging engine speed are increased for acceleration of the engine. One of the basic pulse widths is retrieved in accordance with the actual engine speed and the throttle valve opening degree, and a fuel injection pulse width is calculated based on the retrieved basic pulse width.

Abstract: The present invention provides a snowmobile with a reverse-shift lever. A shift cable extends between a transmission which is shiftable from a forward condition to a reverse condition and a lever means of the invention. The lever means is mounted on the snowmobile and includes a lever arm having first and second sides which may be moved from a first, forward position displaying its first side and second, reverse position displaying its second side. So moving the lever arm causes the cable to move, thereby shifting the transmission between its forward and reverse conditions. The first side of the lever arm may include an indicator indicating a forward condition of the transmission and the second side of the lever arm may be provided with an indicator indicating a reverse condition.

Abstract: A multiple driven axle vehicle, such as a four-wheel drive recreational vehicle having its front, steerable wheels being optionally driven by providing double acting overrunning clutches in the hubs of the front wheels. A transmission mechanism is provided for driving the front, optionally driven wheels slower than the driving surface otherwise drives those wheels so that the slower driven wheels overrun and do not engage when the steerable wheels are turned as the vehicle is driven through a turn, thereby eliminating the need for a differential between the steerable wheels and between the front and rear wheels. The overrunning roller clutches of the optionally driven hubs desirably include an intermittent friction apparatus operative between the roller cage and the vehicle chassis to intermittently exert a force tending to retard rotation of the cage with respect to the chassis, thereby indexing the roller cage and rollers to the forward or reverse engagable position.