I have a MT35 and it runs good. What I did to mine was I replaced the ignition with a rexcel and set the timing to 28 degrees btc that fixed a lot of problems also changed the spark plug and gaped to 20 you can also check your pluming for the fuel tank. make sure that the vent line has a loop around the fuel tank to prevent the fuel from siphon out. And adjust your carb (not like A glow engine) open the throttle all the open and adjust the high end needle to max rpm then bring it down to idle and adjust the low end to the highest rpm. Then move the throttle up if it bogs down and then picks up rpm its to rich on the low end lean it out, if it dies out its to lean open the low end needle ( adjustments on the needles should be about the 1/8 turn at a time wait a few seconds between each adjustments and try it again) Also there is a sticky in the gas engine forum ( gas engines for dummies) read that and read it again one more thing is to check the screen in the carb under the cover that has the one screw make sure its clean and use a felt fuel filter in the fuel tank and one in the fuel jug. also when you are done flying for the day do not run the engine dry like a glow engine just close the choke and let it die that keeps the rubber membrane in the carb from drying out and your fuel lines flexible that's what I do hope it helps you michael