This post is to help anyone with the same problem. My grandson has a 500 Scrambler that wouldn't idle. After cleaning the carb twice and scratching my head wondering what was wrong, I happened to see wires going to the throttle. When taking off the throttle cover I see a set of points. If your throttle cable has too much slack the points close and shorts out the ignition. If you are having the same problem I hope I gave you the answer.