So, im confused. I got the original carb back on it about a year ago, and the idle is still screwed up. When the engine is cold starting, it stalls within seconds if I don't control the throttle, and when it's warm, it revs up uncontrollably unless I turn the idle screw way down, then it stalls, if I don't control the throttle. It has a really cheap Chinese air filter and I think that it's restricting airflow to the engine. Would that be a possible issue, or what else could it be?