jbright is right, HS needle too rich. these engines tune backwards from most.
set the bottom and forget it. tune with the top.

found the same thing yesterday with a buddies full mod. kept flamin' after it started, notice raw fuel spitting out the stinger. started leaning it got better and better. then sat there and idle for like ever. threw it down busted the throttle went like a banshy. no more probs the rest of the 98 degree 55% humidity brutal day. very nice engine. mine will be on order soon as i can dump these speeds.