I have a .15 o.s cv-x max engine and it is tuned properly but it wont idle for more than 10 seconds when i start to play with it. If i were to let it sit there it will idle for a whole tank of gas but as soon as i start to rev it up a couple of times it will shut off. my friend (expert) has been in the world of rc's way longer than me and he keeps on saying that it has something to do with the clutch. He says that there is a spring that i need to buy for the clutch. is this true and can somebody tell me if it has something to do with the clutch.