Abstract: An air cleaner backing plate for coupling to an engine disclosed herein includes a first side to be coupled to an engine and a second side opposite the first side. The backing plate further includes an intake aperture to be aligned with an air intake port of the engine and a tube coupled to the backing plate. The backing plate may further include a reservoir and/or a circular attachment coupled thereto.

Abstract: A combination backing plate and crankcase breather for a motorcycle engine having at least a pair of cylinders, a cylinder head mounted on each cylinder and a valve for connecting each cylinder head to the crankcase for venting the crankcase through an exit port in the cylinder head. The combination includes two hollow bolt alignment members integrally connected by brackets to a support member. The support member includes a venturi air intake, an air cleaner support surface and a backing plate. The backing plate is adapted to allow the support member to be mounted to the air intake of the motorcycle engine. The air intake of the motor cycle engine may be connected to a carburetor or a fuel injection system. The air cleaner support surface is adapted to allow an air cleaner and air cleaner cover to be mounted to the combination.