Let's talk about idle mixture and its affect through the range...

[Shuriken]

Most carbs I have worked on seem to have well-defined circuits. The carb circuits on the Max seem to have way more overlap... For example, the idle mixture settings seem to produce a very noticeable effect on performance outside of idle. The question is why?

If I turn the screws out to 3.5 turns and try to get the bike into VBoost, it sputters and won't boost. I can only assume that these carbs draw fuel from more than just the main jet passageways above mid throttle?

 

[maleko89]

Are you creeping into Vboost or WOT?

At mid throttle pilot mixture still has a small effect up to 5000 rpms or so. When vacuum drops below a certain point the pilot circuit is shut off. When the throttle valves are at idle position or 1/8 throttle then there's high vacuum and mixture is pulled from mixture screw hole that's below the throttle valve.

 

[Shuriken]

All I know is that on my setup, if I have the mix screws out too far, I can't get the bike past 50% throttle...... weird but reproduceable problem...