Alright guys,
I've got a race on Sunday and only half the day tomorrow to work on this. My throttle is sticking once it runs for five minutes. Its fine when its first started, but once it warms up, it sticks at the bottom end. I had this problem once before but it was sticking at half throttle. It ended up being a burr in the right carb hanging the butterfly up. I had it polished out and it was fine.
I know its not the cable because once its running, the throttle cable cam goes all the way back to the idle stop. I've got lubricant on the cable, and its fine, plus I've sprayed the return springs inside the housing and the one that is in between the two carbs. Please help, I don't want to have to grind the butterfly again. Thanks guys,

 

I would take the carbs off and check visually for proper butterfly action while applying throttle. If everything is smooth, then you have eliminated the butterfly and can move too the slides. Should be a piece of cake.