One way that will usually give you a clue as it too lean or too rich is. After adjusting high speed needle lift plane so nose is vertical. If too lean it will lean out even more and heat up. Open needle another 1/4 turn then try again. If you continue to have a problem it maybe it's sucking air someplace that is leaning it too much. If so find outwhere the air leak is or will never get it tuned. Once you get it running perctly at high full throttle then you can adjust low speed needle (not before). To adjust low needle bring the throttle trim up a bit so it's running a bit fast at idle. now bring trim down a bit to slow it to normal idle. If still running well. (you should be able to ell by the sound if it's loading up or going lean). If all seems good then advance throttle quickly from idle. It should come right up smoothly. If it quits then idle needle is too lean, if it sort of gurgles coming up, too rich. You will get just takes practise and a good ear for what it should sound like. If none of this works,GO ELECTRIC HAA HAA.