Patent attributes
A throttle body is connected to a rear portion of a cylinder head of an air-cooled engine, and a fuel pump is disposed in front of the engine. The fuel pump is such as to be disposed below a fuel tank 6 such a manner as to be separated therefrom and to be integrated with an auxiliary tank. Fuel is sent under pressure from the fuel pump to the throttle body via a fuel feed tube, and surplus fuel is returned to the integrated auxiliary tank, consequently, no piping for return fuel being required. Vapor generated in the fuel 23 returns to a space above a fuel level resulting when the fuel tank 6 is filled up via an exclusive return tube and is, therefore, prevented from mixing into fuel.