Abstract: A V-twin engine having a crankcase and a pair of cylinders defining a V-space therebetween, wherein the V-space is substantially enclosed, and a carburetor is positioned within the V-space. An intake air preheating arrangement supplies heated intake air to the carburetor, and a carburetor heating arrangement heats the V-space and the carburetor which is positioned within the V-space. Each of the foregoing arrangements, used separately or in combination within one another, aids in preventing “freeze-up” of the carburetor during running of the engine in a cold environment.

Abstract: A V-twin engine having a crankcase and a pair of cylinders defining a V-space therebetween, wherein the V-space is substantially enclosed, and a carburetor is positioned within the V-space. An intake air preheating arrangement supplies heated intake air to the carburetor, and a carburetor heating arrangement heats the V-space and the carburetor which is positioned within the V-space. Each of the foregoing arrangements, used separately or in combination within one another, aids in preventing “freeze-up” of the carburetor during running of the engine in a cold environment.

Abstract: A V-twin engine having a crankcase and a pair of cylinders defining a V-space therebetween, wherein the V-space is substantially enclosed, and a carburetor is positioned within the V-space. An intake air preheating arrangement supplies heated intake air to the carburetor, and a carburetor heating arrangement heats the V-space and the carburetor which is positioned within the V-space. Each of the foregoing arrangements, used separately or in combination within one another, aids in preventing “freeze-up” of the carburetor during running of the engine in a cold environment.

Abstract: A V-twin engine having a crankcase and a pair of cylinders defining a V-space therebetween, wherein the V-space is substantially enclosed, and a carburetor is positioned within the V-space. An intake air preheating arrangement supplies heated intake air to the carburetor, and a carburetor heating arrangement heats the V-space and the carburetor which is positioned within the V-space. Each of the foregoing arrangements, used separately or in combination within one another, aids in preventing “freeze-up” of the carburetor during running of the engine in a cold environment.

Abstract: An air cleaner for small internal combustion engines, including a removable or replaceable air cleaner element detachably mounted within an air cleaner cavity which is defined at least on part by the shroud of the engine. The air cleaner element includes engagement structure for releasable engagement with a wall of the air cleaner cavity to permit mounting of the sir cleaner element within the cavity, and removal of the air cleaner element from the cavity, without the use of tools. In addition, a cover is provided for releasably engaging the air cleaner cavity to cover the air cleaner element.

Abstract: A small internal combustion engine having user interfaces which are located proximate to one another and within a centralized portion of the engine which is easily accessible by a user, such that the user may readily identify and manipulate the user interfaces. The user interfaces include the carburetor choke and throttle controls, the carburetor primer bulb, the engine ignition key switch, the fuel shut-off valve, the fuel fill inlet and fuel tank cap, and the oil fill inlet and oil fill cap. The carburetor choke and throttle controls are configured as rotary members mounted within an upper front portion of the engine shroud, and are shaped for easy grasping by a user to control the running of the engine.

Abstract: An air cleaner system for small internal combustion engines, including a removable or replaceable air cleaner element detachably mounted within an air cleaner cavity which is defined at least in part by the shroud of the engine. The air cleaner element includes engagement structure for releasable engagement with a wall of the air cleaner cavity to permit mounting of the air cleaner element within the cavity, and removal of the air cleaner element from the cavity, without the use of tools. In addition, a cover is provided for releasably engaging the air cleaner cavity to cover the air cleaner element.

Abstract: A small internal combustion engine having user interfaces which are located proximate to one another and within a centralized portion of the engine which is easily accessible by a user, such that the user may readily identify and manipulate the user interfaces. The user interfaces include the carburetor choke and throttle controls, the carburetor primer bulb, the engine ignition key switch, the fuel shut-off valve, the fuel fill inlet and fuel tank cap, and the oil fill inlet and oil fill cap. The carburetor choke and throttle controls are configured as rotary members mounted within an upper front portion of the engine shroud, and are shaped for easy grasping by a user to control the running of the engine.

Abstract: An air cleaner system for small internal combustion engines, including an air cleaner element which is received within an air cleaner chamber formed within a cover member of the engine. A substantially transparent cover covers the air cleaner chamber and permits viewing of the air cleaner element therethrough, such that an operator may easily determine whether the air cleaner element needs to be replaced. In another aspect, a cover member for attachment to the cylinder head of an engine is provided to define a rocker chamber therebetween, the cover member including a wall portion extending therefrom along the engine cylinder to define an air cooling passage or duct between the wall of the cover member and the engine cylinder. The wall of the cover member directs cooling air downwardly and closely about the engine cylinder to aid in cooling the engine cylinder.

Abstract: An oil fill tube for an internal combustion engine, the engine including an oil sump contained therein. The oil fill tube is axially flexible, and includes an extendable and contractable accordion section intennediate first and second ends, the first end sealingly affixed to a fill hole in the engine housing such that oil may be filled through the oil fill tube into the oil sump. The flexible, extendable, and contractable accordion section of the oil fill tube allows a single oil fill tube to be used with a variety of differently sized engines, and also dampens relative vibration between the crankcase and shroud of the engine housing to reduce tension on the fitting between oil fill tube and crankcase and to prevent oil leakage therethrough from the oil sump. A variety of fittings between oil fill tube and crankcase provide a secure, leak-resistant connection therebetween.