Confirmed by a recent experience that Jody helped me with, I'd never re-tune to solve a problem like that. If you are confident it was tuned well, and I bet it was, then start looking for the real problem. In my case it was crap in the screen...caused I think by Hayes neoprene. Not 100% sure what caused the crap in the sceen, but 100% sure it was crap in the carb screen that caused my woes (wouldn't transition, very high idle, wouldn't hit peak RPM's anymore, dead sticks). The screen is one of many things that could cause it. Could be the carb bolts loosened up and/or a gasket problem. As mentioned it could be ignition area too. That includes batt, switch, spark plug (doubtful), ignition module. Could be tank plumbing. Hope you're not using Hayes neoprene. This caused the same problem in my DL-50 and DLE-55. Was not the engines problem at all and Jody was very helpful.