Originally Posted by NYgoneCA
The repair manual (its not clymers..the other brand..i forget) refers to the part as the air pilot screw. Thats what I was going off of.
This is correct...they are pilot air screws, according to Clymer's. They control A/F mixture at small throttle openings. I'm not sure if they do this by restricting air, or by adding fuel or vice versa, all I know is that turning them CW leans out the mixture, CCW enrichens it. That's why we turn them out after 'coastering' and removing the EPA crap..to lessen the popping because of lean mixture when the throttle is closed.
NY... our stock main jets are 132s, and I've heard riders using anywhere from 140 to 160 w/ the ear shave. There's lot of info on VROC and in our Yahoo group re sizes, needles etc. Check it out...
My intake & carbs are stock except for K&N air filters...I've not done anything because I was afraid of exactly what you've posted, and the Vulc runs great, a little on the lean side, but great. Because the main jets are easy to change, I am
going to go up to 135s soon just see if I can remove the very slight popping I still get after yanking the EPA crap and turning the mixture screws out to 2 3/4 turns. I figure that small of an increase won't hurt anything, and the bit more fuel could even be a good thing...