How do i tune the engine of a savage 25 engine? I have a savage 25 but I upgraded to a k star 4.6 high output motor. The engine is completely broken in and starts fine, but is way out of tune. I just took it into hobby town usa and it was working fine but it is running fine but once i go over 3/4 throttle it burbles and starts to stall. It moves on its own without giving it throttle, so I am guessing it is running lean. I tried to adjust the throttle trim on the controller, but that did not do much. How do I make it so it can stay in the same place without giving it throttle, and make it so i can go over 3/4 throttle without it burbling and losing all power?