Reducing the MAJ orifice size is tuning the AF toward richness in the emulsion tube - therefore richer AFR at all main fueling circuit ops. Problem I had was that there was no info - that I could find - on what the tuning method should be. I know the tuning method for enriching the AF with progressively larger main jets. And as far as I can tell, the end results would be identical - so I went with what is known, larger main jets until AFR is charted(proven) to be correct.

 

OK, I'll see if my a/f is drifting one way or the other as rpms climb and go from there.

Compounding the end result is the fact that cranking it open at mid to low rpm-which removes the needle taper effects (since it's now at one position/WOT) vs opening throttle more and more kind of places all the work load on the main jet. Meaning what's too rich at less than WOT may be perfect at high rpm,

- One tuner's article suggests removing the main jet altogether for testing, saying the bike should run cleanly up to about 3/4 throttle as you open it progressively (if the needle position is correct) before the lack of a mj has it stumbling.