Abstract: A charge forming device for a combustion engine includes a throttle body having a throttle bore, an air passage having at least a portion in which air flows separate from the throttle bore and a throttle valve with a valve head movable relative to the throttle body. A nozzle body has a fuel passage and a feed passage, the fuel passage is arranged to receive fuel that exits a fuel outlet of a fuel metering valve, and the fuel passage is communicated with a fuel chamber through which fluid flows into the throttle bore, and the feed passage is communicated with the air passage to receive air from the air passage and the feed passage is communicated with the fuel passage upstream of the fuel chamber, wherein air in the feed passage is mixed with fuel in the fuel passage upstream of the fuel chamber.

Abstract: A throttle body has a throttle bore with an inlet, an outlet and an air passage. A throttle valve has a valve head received within the throttle bore. A fuel metering valve is mounted on the throttle body and has a valve element and a fuel outlet, the valve element is movable relative to a valve seat to control fuel flow through the fuel outlet. And the nozzle body is carried by the throttle body and has a fuel passage and a feed passage. The fuel passage is arranged to receive fuel that exits the fuel outlet, and is communicated with a fuel chamber through which fluid flows into the throttle bore. The feed passage is communicated with the air passage and with the fuel passage upstream of the fuel chamber. Air in the feed passage is mixed with fuel in the fuel passage upstream of the fuel chamber.

Abstract: In at least some implementations, a fuel metering valve, includes a bobbin defining a passage and having one or more voids in the surface of the bobbin that defines the passage, aa wire coil around the bobbin and an armature. The armature is received within the passage in the bobbin and movable relative to the bobbin from a first position to a second position when electricity is supplied to the wire coil.

Abstract: A throttle body has a throttle bore with an inlet, an outlet and an air passage. A throttle valve has a valve head received within the throttle bore. A fuel metering valve is mounted on the throttle body and has a valve element and a fuel outlet, the valve element is movable relative to a valve seat to control fuel flow through the fuel outlet. And the nozzle body is carried by the throttle body and has a fuel passage and a feed passage. The fuel passage is arranged to receive fuel that exits the fuel outlet, and is communicated with a fuel chamber through which fluid flows into the throttle bore. The feed passage is communicated with the air passage and with the fuel passage upstream of the fuel chamber. Air in the feed passage is mixed with fuel in the fuel passage upstream of the fuel chamber.

Abstract: In at least some implementations, a fuel metering valve, includes a bobbin defining a passage and having one or more voids in the surface of the bobbin that defines the passage, aa wire coil around the bobbin and an armature. The armature is received within the passage in the bobbin and movable relative to the bobbin from a first position to a second position when electricity is supplied to the wire coil.

Abstract: In at least some implementations, a charge forming device for a combustion engine includes a throttle body and a throttle valve. The throttle body has a throttle bore with an inlet through which air flows into the throttle bore and an outlet from which a fuel and air mixture exits the throttle bore. The throttle bore has a throat between the inlet and outlet and the throat has a reduced flow area compared to at least one of the inlet and outlet. The throttle valve has a valve head received within the throat of the throttle bore and movable relative to the throttle body between a first position and a second position wherein the flow area between the valve head and the throttle body is greater when the valve head is in the second position than in the first position.

Abstract: In at least some implementations, a method of controlling spark events in an engine includes determining for at least two engine revolutions in a four-stroke engine at least one characteristic of the primary coil voltage for a spark event, determining, based upon the characteristic of the primary coil voltage, which of the spark events is associated with a compression phase and which of the spark events is associated with an exhaust phase of engine operation, and providing spark events in subsequent engine revolutions that are associated with the compression phase of engine operation but not in revolutions associated with the exhaust phase of engine operation. In at least some implementations, the characteristic is the duration of the spark event as determined by changes in the primary coil voltage, and the characteristic may be that the duration that the primary coil voltage is above a threshold voltage.

Abstract: In at least some implementations, a charge forming device for a combustion engine includes a throttle body and a throttle valve. The throttle body has a throttle bore with an inlet through which air flows into the throttle bore and an outlet from which a fuel and air mixture exits the throttle bore. The throttle bore has a throat between the inlet and outlet and the throat has a reduced flow area compared to at least one of the inlet and outlet. The throttle valve has a valve head received within the throat of the throttle bore and movable relative to the throttle body between a first position and a second position wherein the flow area between the valve head and the throttle body is greater when the valve head is in the second position than in the first position.

Abstract: In at least some implementations, a charge forming device includes a main body, a throttle valve and an adjuster. The main body includes a main bore through which fluid flows for delivery to an engine. The throttle valve is carried by the main body and moveable relative to the main bore to control fluid flow through the main bore. And the adjuster is moveable relative to the throttle valve and engageable with the throttle valve to adjust the range of motion of the throttle valve. In at least some implementations, the adjuster limits the range of motion of the throttle valve when the adjuster is engaged with the throttle valve.

Abstract: In at least some implementations, a charge forming device includes a main body, a throttle valve and an adjuster. The main body includes a main bore through which fluid flows for delivery to an engine. The throttle valve is carried by the main body and moveable relative to the main bore to control fluid flow through the main bore. And the adjuster is moveable relative to the throttle valve and engageable with the throttle valve to adjust the range of motion of the throttle valve. In at least some implementations, the adjuster limits the range of motion of the throttle valve when the adjuster is engaged with the throttle valve.

Abstract: A carburetor includes a main body defining a bore, a main passage and a venturi defined within the bore, and a fuel nozzle carried by the main body and including a fuel nozzle outlet communicating with the venturi. The carburetor may also include a valve member translatable across an axis of the bore, such that in a closed state, the valve member closes the main passage but maintains the venturi at least partially open. The carburetor may also include a needle valve disposed at an end of the fuel nozzle substantially opposite of the fuel nozzle outlet to variably control flow of fuel into a fuel nozzle inlet, and a needle valve transmission may be coupled between a throttle shaft and the needle valve to convert rotation of the throttle shaft to translation of the needle valve.

Abstract: A carburetor includes a main body defining a bore, a main passage and a venturi defined within the bore, and a fuel nozzle carried by the main body and including a fuel nozzle outlet communicating with the venturi. The carburetor may also include a valve member translatable across an axis of the bore, such that in a closed state, the valve member closes the main passage but maintains the venturi at least partially open. The carburetor may also include a needle valve disposed at an end of the fuel nozzle substantially opposite of the fuel nozzle outlet to variably control flow of fuel into a fuel nozzle inlet, and a needle valve transmission may be coupled between a throttle shaft and the needle valve to convert rotation of the throttle shaft to translation of the needle valve.