Any help is greatly appreciated.

I have a new hellfire rtr it has a stock engine but I put on a rotostart and aluminium clutch (with weights) before starting break in of the engine. I am finding that I can't keep the engine running properly to do a break in correctly. At first I couldn't get it to start after several attempts.

After this it started firing up but would go nuts and start revving like mad with the throttle right down. I had to pinch the fuel line to cut it off as it was revving like crazy unless I had the breaks on and wheels turning on the idle.

It seems to be running a bit lean when it idles and not giving out much smoke but when it gets going and revs for a bit it puts out smoke if the revs are increased.

I haven't been able to get the engine running for more than 40 seconds to start breaking it in.

I just got the SavageX 4.6 and had the problem of getting it to start. It was running to rich. I ended up turning the high speed screw all the way in and then bring it out 3 turns. I think I ended up with it about 2 3/4 turns out before it would run for break in.

first off check you throttle trim on youre controller and make sure its low then then the close the low speed neddle and turn it all the way in just snug and 2 and a half turns out then try to fire it up

I would've put the new clutch on after breaking in the engine to see how much peformance it boost compared to the stock ones, its alot more fun to upgrade and see peformance.