I think the bike accepts a H4 bulb right?
If thats the case, you could replace it with Osram silverstars, or if you really wanted it, an HID kit. I'm not certain that I'm right about the bulb, and it may have changed at some point in the ninja's model run. In any case, it *is* removable, so you can replace it with something more powerful and/or fruitily colored. Somebody confirm!