Hi there jamiebravo: I have The same Evolution engine, and it took me a while to get a handle on the needle valve settings. Through reading some RCU forums, I finally had all the mechanical needle valve restrictions removed along with the flywheel weight. Have quite a few hours of air time on the engine now, and have noticed a rich mixture in flight when going to half throttle. Another RCU discussion revealed that there is a mixture problem in the mid throttle range. The discussion commented on that after getting the high speed needle valve set properly, and the idle mixture set, that there was a rich transition from idle to max throttle. A couple of dead stick landings made me gun shy about lowering the idle rpm below 3000. My last trip to the club field, I lowered the idle to 2800 which seemed to be ok as far as becoming a deadstick pilot on final. Still the 10x5 prop and idle rpm makes for a high landing speed with my old heavy trainer. My high speed needle valve is set 200-300 rpms above the 4 cycle break. With added castor to my 10% Nitro all castor fuel, there is no problem locating the plane with such a smoke trail. I think someone suggested changing carbs to get the mid range mixture problem. I am using a Fox Miracle glow plug which is somewhat hot.

Let us know what you find fixes your problem.

Rich S.
A & P mech