I have the 1040 pipe that is in my sig, it's the one suggested by OS just for this engine.

I have the Mixture Control Valve and the Metering Needle set to the base spec per the manual. I have only been messing with the Needle valve during break-in and tuning as the manual also states to do.

I started with the Needle valve 2 full turns out from closed, which is the base setting for break-in. Then for the first 7 tanks I only closed it 30 degrees each tank as the manual suggested which after 7 tanks left me a little over 1 full turn more towards closed than the start position.

I'm now in the final adjustment portion of the manual, page 21. It says to do straight hi-speed runs turning the Needle valve closed an additional 30 degrees until it starts to loose power and not smoke much, then open it back 30 degrees.

This is where I am stuck at because every time I try a run, soon as I let off the throttle the idle is crazy high and I have to turn down the idle screw to get it normal, then it stalls. So I have to increase the idle with the screw again to get it to start and then try another run, same thing. Very frustrating.

Any ideas what the problem is?