marshrabbitt,

assuming you are using a puller prop and that should be a 14x8 since its a new engine. Close the HSN fully and then open 3 turns. Start the engine and let it run at full throttle for a few seconds. Then very carefully (watch out for the prop) slowly close the HSN. You should hear the engine exhaust pitch rise and then drop. When it drops you are too lean, so open it back up till you hear the pitch rise again. If it goes to the max and then drops, now close the needle to get the max again. Once you achieve the max engine pitch open the needle 1/4th turn. That would be your setting.

We open the needle back from max rpm because the engine will unload in the air (run a bit faster as the load will reduce once in motion) and for some safety to keep the engine rich. We assume you have not touched the LSN screw yet. The factory set for that is rich, leave it there. You will need to repeat the same once in your airplane, do it with a helper holding the airplane vertically up as this is the worst position for the engine from the fuel draw point of view (most chances of going lean in this position). While not everyone will agree to this, preferable to use synthetic-castor mix in these larger engines and use minimum nitro (2-5%) for more relaible operation.

If I were you I wouldnt run in the backyard (though I did do it in my appartment yesterday for a few seconds) lest the neighbours complain.

Ameyam