To figure out if its to lean do something along the lines of this:
At full throttle give the plane a 45 degree angle. If it revs and then dies, with no smoke too lean. If it revs and dies with smoke it's too rich. Just get where it will rev and keep going
someone please correct me if i am wrong.

The setting should be between 1-2.5 turns. Run it quit rich your first few flights, it takes almost a gallon of fuel to fully break in an engine