i have about a quart of O'Donnel fuel through this thing and the piston still feels incredibly tight. the other thing is - the motor doesnt really perform well unless its on the lean side, kinda makes me nervous. it will have marginal speed and run very cool 190-200. i closed the needle no more than a 1/16 of a turn made 2 passes and it shot right up to 260. turned it back 1/16 of a turn and it cooled right off. very sensitive. oh, one other thing and this might be important.-when i take my temp readings i have been pointing the laser down into the top of the head,right where the plug seats-the hottest part of the engine. is that the correct way to read theses motors?