If you set the HSN and LSN back to the defaults (3 1/2 turn out for the HSN and the LSN should be out flush with the throttle arm). Warm the motor up and start leaning the HSN our (turn clockwise) 1/8 a turn at a time. Each time, take it for a high speed run and see how it runs. I think mine is leaned out about 1 1/4 turns from there. Just watch the temperature and make sure it does not get too hot. I have read where you should run it at 1/2 a tank of gas while fine tuning to help with the motor leaning out on it's own as the fuel level drops. I pushed mine up to about 250-260 when it ran out of fuel. As you adjust the HSN you will feel the power coming in with each turn. Once that is done, adjust the LSN. This will help with the takeoff. Also, once you get another 4 or 5 tanks through it, the motor will start to perform even better. I have my MT2 pretty close. The ATX still needs a little tweaking but it's getting there.