[turbotom123]

If you are running a header tank made by thunder tiger than you may want to check the top nipple on the tank. During molding there is a flap of plastic that ends up clogging the port and you have a lean running problem. You may also want to check all the head bolts for tightness. Also check the bearings, i have a friend who was having a similar problem and he sent the motor off and the front bearing was sucking air causing it to go lean and bog. Also some of the professional pilots from miniature aircraft told me that most hypers when broken in the main needle valve will be one full turn and about 5 clicks out from closed. They also told me that you do not want the motor to get over about 180 deg F. Anything over that and you are just taking life out of the motor. Hope this helps.