Slow idle screw?

I have what I think is described as a 'smooth bore' set of Mikuni carbs on my KZ650B - on the top of each carb is a small screw adjuster which I think is described as the slow idle screw? What is the correct amount of turns out from gentle seating on these? Is it 1.5 - 2? I read somewhere that to get these adjusted right you set the rpm a little high then adjust them until rpms are highest then back the throttle adjuster down to the idle you require - sound right?

Finally, on an older bike like this, would it be better for me to set the idle a little higher?


Lee

What year is your KZ?
I have a 79' KZ 650 B3, my manual says its suppose to be 1 5/8 turns from seated. To adjust idle you should only use the idle screw on the top middle of the carb assembly. It also says that the air idle screws should not need to be adjusted to correct any engine running problems. Once you have the air idle screws set you should do a vacuum test on all four carbs to make sure they are all the same. To make them the same use the air idle screws to set the vacuum.

bubbap wrote:

Once you have the air idle screws set you should do a vacuum test on all four carbs to make sure they are all the same. To make them the same use the air idle screws to set the vacuum.

Are you referring to carb synchronizing/balancing? Balancing carbs is done by adjusting throttle valves inside carb venturi not by adjusting air screw (which adjust the idle mixture i.e. air/fuel -ratio).

Balancing is usually done by connecting some kind of a vacuum gauge / manometer to each intake throat and balancing the vacuum in all carbs to same level by adjusting throttle valve opening in all carbs.