Re: How to know when broken in? Fuel ratios?
I agree... These engines aren't anything so special that the oil ratio needs to be ultra precise or that only certain brands etc will work... You could probably save the used oil from doing your car's oil changes and they'll run just fine on it. You will Not blow your engine if you accidentally or intentionally grab a bottle of marine 2 cycle oil either.
I already know that at 10,000 rpm the rings and cylinders aren't going to last very long, but I just put new rings in, re hone the jug, and I'm good for another 6 months or so...