stalling-some times

[dwint51]

a few months ago I was riding and all of a sudden it had no power and stopped and stalled.thought it was a coil but it started back up and every thing was good.today I was riding for maybe three minutes and when I gave it gas it was dying .I let off the throttle and it was fine.my air cleaner and carb are clean.i don't know if it sounds like a loose connection or is something going out.if it is a connection where should I look