Check here: http://www.bmeengine.com/html/manual.htm

Start with both needles about two turns out. Then set your high speed needle for max rpms, then richen it about 1/8 turn; no more. Then adjust your low speed needle until it will idle smoothly without loading up. It should idle for at least a minute without slowing down or quitting. Then try "gassing it" to see how the transition is to higher rpms. If it hesitates, richen the low speed needle slightly and try again. Richen the low speed just enough that it doesn't hesitate on the transition. Then check the high speed needle setting again. It will most likely have to be fine tuned again. Check the idle and transition once more, and go fly.

AV8TOR