Scooterotica

On a PHBH carb, which way do you turn the mixture screw to weaken the mix?
Because I just read 2 different things on the interweb that gave different opinions.

On my PHBH28 screw in to weaken............

It all depends where the screw is.
If is near the venturi, screw in to rich and screw out to weak.
If is near the manifold, is the opposite function.

Interesting, one article I read said that if the screw is at the back then you are adjusting the air flow and that screwing in will make it richer and out leaner. :wtf:

as giankx, I've always gone with the general rule that if the screw is behind the slide, it's a mixture screw, so in to weaken; if it's at the front, it's an airscrew, so out to weaken...

try it right in, and then say 3 turns out; that should tell you which way is which... if it doesn't seem to be making any difference, you may need a different size idle jet anyway...