Well i've been learning a lot about this engine the last few days.I was adjusting the throttle travel screw instead of the idle needle. The hi speed needle became harder to turn so i took it out and cleaned it along with the idle, and fuel intake ports.this cured the problem perhaps it was gummy from fuel deposits.Once all back together the engine would not start.After about an hour of spinning and flipping the prop i found that the glow plug was registering but not heating.I changed it.The engine would now start but not until i put fuel in the carb.and even then it would only run backwards.I know that this is an indication of a rich mixture on a two stroke i suppose that this is also the case for four strokes.I began adjusting the "right "idle needle valve but the same thing happens.It won't start until i prime it and then it will only run backwards.I've been to both extremes with the idle setting and encountered the same symptoms.What am i missing?