I lean my low end needle in till it starts to sag with the throttle advanced quickly. Then richen it up a little till you get smooth fast transition. Thats it, don't run it a little rich, there is no need. All you do is carbon things up, and fowl plugs. Run the high end up to max rpm, and back of just a touch. No need to run that needle rich either. Just make sure its not sagging on up-lines.

Mine has be flawless, 3 years old!