Dave, you're kidding, right? I mean you'll get beatened by a cold salmon by at least half the people in RCU if you run the .46fx or .46ax in four stroke mode. Unless O.S. changed its breaking in instructions, I would follow a very different approach. I would simply fuel it and start it up. Let it run rich for a little while (to let it get up to temperature). Then set the high needle a 5-10 clicks rich and set the low speed needle so it idles confidently. Then fly. I don't know but that seems to be the attitude for breaking in ABC engines here. I'm sure you'll get lots of different responses but the general idea is don't every four stroke your engine... it is the quickest way to lose compression.