RE: OS 75AX Question
Two to two and a half turns is not the 'required setting' for your engine. That is only a recommended extra rich starting position for the first starts. You must tune or lean your engine from there and how much, no one can tell you since many varibles are at work.
Your manual spells out how to go about the tuning procedure pretty well but you have to read it. Better yet find a local mentor/instructor to help as simple tuning of your engine is a learning process we all must go through.
Depending entirely on one of these forums, while useful is like peeing down a dry well to find water. Network with your local club or find a real live local mentor/instructor.
The AX's are wonderful engines and user friendly.
John