The present invention relates to small-sized vehicles such as motorcycles or motor tricycles having a front portion of a vehicle body covered by a vehicle body cover, and more particularly to a cooling air intake structure for suppressing temperature rise of a carburetor.
Normally, in a motorcycle or the like, an engine is supported by main pipes and down tubes which are connected to a head pipe in a front portion of a vehicle body, and a carburetor is disposed in the proximity of the engine, and one would find many motorcycles in which a vehicle body cover covering the front portion of a vehicle body is mounted in order to improve stream line of running wind.
However, if the proximity of a carburetor is covered by the vehicle body cover, then as a flow of wind in the proximity of the carburetor is little upon running, the temperature of the carburetor is liable to rise due to influence of heat generated in the engine, and when the temperature of the carburetor rises, not only the amount of intake air of the engine is reduced, but also the air-to-fuel ratio varies and the output of the engine is lowered. Accordingly, it is necessary to guide running wind to the space portion where the carburetor is disposed and thereby suppress temperature rise of the carburetor. Especially, a carburetor of a V-type engine is liable to be influenced by heat generated in the engine because the carburetor is disposed in the space portion between the cylinders arranged in a V-shape.