| 摘要 |
PURPOSE:To lead cooling air to desired cooling positions in a cylinder head by a method wherein fins at the introducing side of the cooling air in the cylinder head are arranged along the flow direction of cooling air from a ventilating fan and are formed so as to be inflated more largely than the fins at the opposite side. CONSTITUTION:The air-cooled engine for motor scooter is covered by a fan cover 61 and the cooling air, ventilated by a cooling fan provided at the side surface of a flywheel, is directed toward the cooling fins 83 by an air leading plate 75. The cooling air introducing side fins 83a, among the cooling fins 83 in the cylinder head, are formed along the flow direction of the cooling air and are more inflated upwardly than the fins 83b at the opposite side. As a result, the cooling air is regulated in the flow thereof and is led to the central section of the cylinder head 32 and the peripheries of plugs, therefore, these sections may be cooled efficiently. |
