Run your engine about 500 rpm shy of max lean rpm and that should be sufficiently rich in a 2 stroke setting.

I saw a gentlemen at field last week take a brand new plane with never run engine, fire it up, set it 500 rpm shy of max lean rpm and take off and fly it 3 tanks worth at full throttle before he fine tuned the idle and transition. He has never broken in an engine on a stationary position. It seems brave to break one in this way but I think I'll do that next time I get a new engine.