theres this chart that someone posted up of the throttle range and when its at certain points what the problem could be like for instance if its from start to 1/4 throttle its probably the pilot jet then 1/4 threw 3/4 its probably your main jet or something like that. did you try searching if not i will try to find it later but someone might chime in with it soon enough
ok i found it pretty easy http://www.bansheehq.com/forums/index.php?showtopic=47286 its a pinned one in the jetting section