I'd open the needle valve a little. Remember, the needle valve needs adjustment based on altitude, air pressure, temperature. Factory setting has never been 100% on for me.. open the needle (high speed) about 1/4 turn and see what happens...even better, go about 3/4 of a turn, or until it stays running at full throttle, but very rich. Once it warms up, SLOWLY close the needle until the RPMs peak (you should be able to hear it, no need to tach it). Once you peak, back off about 1/4 turn. This will leave you in good shape when the engine 'unloads' in the air.

Hope this helps you