It would appear that you have at least a grasp of what lean and rich mean. That's good. In lieu of having the factory settings, you can figure out what the needles actually need to be set as long as you can get the motor to start, idle, and run.
I checked it, but it was rich on bottom and lean on top.
I believe the mixture control valve is the one that's recessed into the throttle barrel and requires a small screwdriver to get at.
Actual needle settings vary from heli to heli, muffler to muffler, day to day, and depend a great deal on the fuel you are using. You'll get different answers simply due to the nitro percentage you have chosen to use.
To set your needles:
Maintain idle at low throttle using the throttle trim on your TX, not the low speed needle. Adjust the low speed needle so that the motor transitions from idle up to about hovering RPM smoothly without blubbering, sputtering or just suddenly dying.
Blubbering and sputtering means the low speed is too rich. If the motor just dies suddenly, or hesitates, the low speed needle is too lean.
Once you get the low speed set about right, lift off and go to full speed, and determine if the motor is too rich, or too lean. Adjust the high speed needle accordingly.
The two needles interact to a large extent. Re-tweak each one until you get them balanced well.
You may be able to lower your throttle trim to maintain a decent idle as you get the two needles properly set.
Run the motor for 30 seconds or more to make sure it's up to operating temperature, then drop the motor down to idle. Let it sit, idling. If the motor slows down gradually, the idle's too rich, if it speeds up a bit, the idle's too lean.
Finally, you can perform the "pinch" test. After you have the motor up to operating temperature, let it sit at idle. Pinch the fuel line. The motor should continue to idle for about 3 to 5 seconds before it begins to speed up and die. If it runs much longer, the idle is too rich. If it goes much shorter, the idle is too lean.
As for factory settings, the manual's way out of print, you'll have to find someone with a copy to help you.
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