1.  Field of the Invention
The present invention relates to a headlamp for a two-wheeled vehicle.  More particularly, the present invention relates to headlamp for a motorcycle or similar vehicle. 
2.  Description of the Background Art
A headlamp for a two-wheeled vehicle is known which is provided on a front cowl.  A headlamp for a two-wheeled vehicle of this type is disclosed, for example, in Japanese Patent No.  3343698. 
FIG.  17, which corresponds to FIG.  6 of Japanese Patent No.  3343698 except the parts have been renumbered, is a front view showing a headlamp 302 for a two-wheeled vehicle in the related art.  There is shown a two-wheeled vehicle in which a front portion of a vehicle body is covered by a front cowl 301 from the front of the vehicle body to the side of the vehicle body, and a headlamp 302 having an inverted trapezoidal shape is provided at the face of the front cowl 301.  Further, an outside air introducing port 304 is also located at the face of the front cowl 301 and underneath the headlamp 302.  A front wheel 303 is located underneath the outside air introducing port 304, such that the outside air introducing port 304 extends across a front wheel 303. 
When operating the two-wheeled vehicle, the headlamp 302 is turned on for drawing the attention of other vehicles or pedestrians when travelling during the daytime as well as during the night time.  Therefore, by improving the visibility of the headlamp 302, the efficiency of the headlamp 302 to draw other people's attention would also be improved. 
In order to improve cooling performance, it is better to provide the outside air introducing port 304 below the front cowl 301, which allows traveling wind to blow onto an engine, a radiator, or the like.  Further, it is better to arrange the headlamp 302 above the front cowl 301 in order to illuminate the front side of the vehicle.  In this manner, the shape of the front cowl 301 is limited due to the aforementioned headlamp 302, the outside air introducing port 304, and the like. 
In addition, the headlamp 302 is an important element for determining a design of the front portion of the two-wheeled vehicle, and hence it is desired to have a shape which gives a novel impression.