Do you have the receiver and transmitter turned on? If you do make sure the throttle isn't open. If thats not the case try adjusting the idle screw. Look into the carb there should only be about a 1mm opening when the throttle is at idle. If that doesnt work, try richening the mixture some. To me though, it sounds like the throttle is already open when you are starting it, so check the carb before you start it next time to see what the gap looks like.