As I said above, if you use the ringed engine style break in on an ABC engine, you won't break the engine. You WILL reduce the power the engine will eventually produce though. For sport flying, most guys really will never know or care if their engine is running 2,000rpm down from where it could have run with a better break in.

So, if you want to run your ABC engine really rich to "break it in", go for it. You won't blow up the motor.

However, if you want to get what the engine can deliver when it comes to power, then you need to do something different.

This IS the beginners forum, and for a trainer, there's nothing wrong with wearing the piston a bit much. But it's funny, I see a lot of guys who come to a competition with an engine they broken in "the way they always did it" and wonder why it is that their new engine is so much weaker than even my old beaters. It's the break-in.

A beginner with their first engine isn't really harmed with a rich break-in. But more information never really hurts, so knowing that there is a another way that will produce more power from future engines isn't a bad thing.