I too agree with Dick. I no longer use break in oils, (synthetic from the start), don't run my engines richer than they need to be and also don't use "break in" props. I do, however limit my 3D flying time to short periods with breaks for pattern type flying in between for the first several flights. In other words I don't do 5-10 minutes straight of torque rolling until I get a little time on the engine. I have done this on a couple big gassers and the engines are running great and look fine on the inside. A friend of mine had been doing this for a long time and all of his engines run excellent, have been reliable and long lasting.