Patent ID: 7363886

Claim:
A power unit including an air-cooled internal combustion engine comprising: a first fan coupled with an end of a crankshaft of the internal combustion engine for cooling at least a cylinder of the internal combustion engine; a second fan coupled with another end of the crankshaft for cooling at least the cylinder; an intake port interposed between a crank case for rotatably supporting the crankshaft and the second fan, the second fan includes a disc fixed to the crankshaft and a multiplicity of blades formed on the surface of the disc on the crank case side thereof, wherein the second fan also acts as a ratchet pawl holder for transmitting the rotation of a starter reel including a recoil starter and a starter case rotatably supporting the starter reel is attached to an adaptor, the starter case devoid of holes on an outer surface thereof, the adaptor including a partition wall and at least a part of the air flow guide integrally therewith, the partition wall disposed adjacent the blades to partition between the crank case and the blades and to form the intake port between it and the crank case; and an air flow guide for causing air flow generated by the second fan to flow together with air flow generated by the first fan after it cools the cylinder as well as guiding a resulting confluent air flow to an exhaust muffler of the internal combustion engine.