I've read all the posts about the 1/5 turn throttle and a crucial point is being overlooked:
It's also a safety feature, especially on the track. Forget the responsiveness and think for a moment about turning that ridiculous stock (on 2011 anyway) throttle WO on a straight. Your wrist is contorted and your elbow is almost pointing in forward! At the end of the straight you have to get that stupid thing all the way back to close and grab 2 fingers of brake, quickly, or you're in a world of hurt. If you have even a sliver of travel left "you're gonna have a bad time".
This happened to me the first day on this bike and it was very costly.
Also, when that bike is pulling off a turn like a freight train and you are only holding on to the right bar with your fingertips cause you have to turn the throttle so far, not only is this dangerous, but your forearm will hate you after a few sessions.
The stock throttle throw basically effs up you're riding position all over the track. If you're not comfortable you're not safe OR fast.
Lastly, the alternative is you buy a kit for $150-$200 and have to spend an entire day changing out the throttle and CABLES.