| 摘要 |
PROBLEM TO BE SOLVED: To improve the cooling performance of an engine by increasing quantity of cooling air. SOLUTION: An under born type motor cycle 1 is provided with a car body frame, which includes a head pipe 2 and a down tube 3, and an engine 12 having a cylinder 12a, which is extended forward in the nearly horizontal direction, is arranged under the down tube 3, and a part from over the down tube 3 to both sides of the engine 12 is covered with a leg shield 34a. In this motorcycle 1, a baffle plate 35, which is inclined backward so as to guide the traveling air to the cylinder 12a, is provided under the down tube 3. With this structure, besides the traveling air, which directly collides with the cylinder 12a of the engine 12, the traveling air, which flows over the cylinder 12a, is guided for cooling to the cylinder 12a by the baffle plate 35, and quantity of cooling air is increased so as to improve the engine 12 cooling performance. |
