I agree, no bore is perfect, even the best racing engine needs a short time to allow the rings to bed in, and the less care that is taken on the honing of the cylinder the longer the running in process.

These motors are very well made, they may be cheaper than the DA's of this world, but the DL, Area 51 etc are all well made. How many posts are there on here that says the motor is turning a 23a prop at 7300 rpm after just 15 mins running, the answer is most of them!

It really bothers me that so called experts tell people new to this wonderfull hobby what is basicaly the best way to reduce the life of their new motor. If you are going to use the motor in competition a week after you buy it, and you need every last 100 RPM, then it may be worth it. But most of us have far more power than we actually need, so waiting a few weeks for the motor to reach its best is no big deal.

Far better to use the best oil you can get, add a little more at the start, then as the motor settles in reduce the oil to the optimum level. This will give you a motor that will last for years giving great performance, flight after flight.

Peter