Give it a chance! I bet is is gunked up a bit inside which would restrict fuel flow at lower throttle settings--- remember it only takes a speck of dirt to wreak havoc with fuel draw. Those are darned good engines I would run the heck out of it before I sold it to Flyboy Dave, because he would show up and have it running perfectly and rub it in...

Run it then run it some more- Heck try some different props. and plugs and give us some stats!

Welcome to RCU!

James