Air mixture screw or Fuel mixture screw??

[godxilla]

I have a DR350. I just bought it recently, it as a Mikuni carb. There is small screw at the bottom of the carb facing up. Is that screw air mixture or fuel mixture screw? Does turning it in (clockwise) make it run leaner or richer?

Any help would be appreciated...

[bg10459]

It's a fuel mixture screw on 4 strokes and an air mixture screw on 2 strokes. Turning it in leans the fuel mixture, out richens it, as opposed to 2 strokes where in is rich and out is lean.

[godxilla]

My bike is the Suzuki DR350 (4 stroke).

So you are saying to turn it OUT for RICHER...??

The guy at the Suzuki dealer said that OUT is leaner....

I am totally confused...any help

[Wayward Son]

out is richer.

[kenyz]

look at it as the fuel screw is covering a gap like a long pin that you screw in/out. as you screw it IN it closes the gap more and more against (lets say the wall) that lessens the amount of fuel it is getting and thus leans the mix by allowing more air/less fuel

out is the opposite, you are opening the gap....providing more fuel and richening the mixture