Hey skyfox: I have a Saito 91 that was acting similar to yours. The instructions called for the low end needle to be 1 millimeter away from the spray-bar. keep in mind I live at 6000' altitude, but this was wayyyyyyy rich I wen't flush with the throttle arm setting, as was suggested by someone here, and what a difference. I have since turned an additional 1/8 turn to lean and it purrrrrrrrrrrs like a kitten. I also adjusted the valves just for s**ts and giggles and the thing is almost spooky now it makes so much power. Both valves were loose by several thousandths from the factory. As was the low end needle. Happy flying: Garry