Forum member 72westie is running his Bullet on the track, and he holds the National Championship #1 plate in the class.
From what I understand, there are some specific rules about Bullets, such as it must have the 4-speed original type gearbox, and it must keep the drum brake, and use a round-slide type carburetor.
Not sure on the other specifics, but maybe 72westie will chime in on this thread.
The Bullets have gotten the National Championships many times since the year 2000, and probably the most championships since that time, of any other bike in the class.