Mikuni 25mm mixture screw?

[DeathRider]

Hi all, we have found out that the problem with my bike cutting out/overheating is the air mixture screw... The problem is that when we couldnt find the air mixture screw on it. ( 25MM MIKUNI CARB) There was 2 screws that we could fine. 1 would get all the fuel out of the carby/bowl etc... And the other which was a phillips head would make it idle higher if u turned it clockwise but anti clockwise would put the idle revs down. Please help!

 

[my67xr]

The Carby is a china Mikuni copy 22/26mm
The fuel screw is at the front underneath the carby near the manifold
A good base line setting is 1.75 turn's out from fully done up.
Most of the Mikuni copy carby's i tune really need a bigger pilot jet, they come with a #15, but respond well with a #20
DHZ sell them for $5 if you want to order one online

I have found the best way to adjust it is to make up a tool, use a small flat head screwdriver bit slipped into some small diameter hose like this