Structure for mounting fuel cock in motorcycle

1. Field of the Invention A structural layout of a motorcycle concerning a fuel tank, a fuel cock, a carburetor, and an engine in relation to a frame is provided. A downward projecting portion is provided on a bottom of the fuel tank towards the rear. The projecting portion extends in a space defined behind a cylinder head and a cylinder head cover of the engine and in front of a rear cross member of the frame. The downward projection is juxtaposed with a carburetor across a motorcycle body. The fuel cock is manually accessible from beneath the one of right or left main frames of the frame.