CV carb air screw adjustment

[AOD]

this is for a kawi bike question, but its running a mikuni type carb simliar on the 80+ GS's.

the problem is the bike wont idle off the choke. the air screws were at 6 turns out, then adjusted to 2 turns out, and it will not start now.

i have suggested a plug swap to make sure this in not a problem.

the question posed now is when you tighen this air screw are you richening the mixture (less air?) or leaning the mixture (more air?)?

any help is appreciated.

~Adam

[Billy Ricks]

The way that circuit is designed turning it in leans it out and turning it out richens it. 6 turns out gets you off the jet altogether. You're completely out of the adjustment range. 2 turns usually gets you into the ballpark. If this is in reference to ice's question he has bigger problems. Poorly adjusted air screws aren't enough to keep it from starting and running. They only smooth out the idle and slight throttle openings. If he had the carbs completely apart he needs to start by doing a decent static sych on the carbs. Use the throttle stop adjuster to get what is usually #3 carb butterfly to just close. Then individually adjust the other 3 using the adjusters on those carbs to do the same. He also needs to be sure the springs, spacers, and clips on the slide needles have been assembled in the right order. He needs to make sure the float level has been adjusted right. Most CV's seem to use 21-22mm as base settings. You measure with the carb upside down and the floats just resting on the float needles, not pushed down. You measure from the gasket surface on the carb body to the bottom of the float. When I say gasket surface I mean the carb with the gasket removed. Remember, with it upside down the bottom of the float is pointing up now.

[Anonymous]

iirc (which I probably don't, easy way to learn is guess wrong, then everyone answers to give the correct one) is that the one screw on CV carbs, on the top of the engine side, is not a screw to adjust mixture, it just adds more of the mix, or less of the mix for idle, it doesn't change the mix of air/gas. At least, that is how I think it works.

Feel free to correct me guys and gals.

[Anonymous]

so i should tear them down, clean em and synch em and that will fix my problem?

[Billy Ricks]

As long as you do everything right it will. You can refer to the carb cleanup series on the GSR homepage. Even though your carbs will be a little different you can still use it as a guide.

[Anonymous]

ive done 2 tear downs before. i dont what can be messed up though as long as you dont lose any parts and dont break anything. what should i keep in mind?

[Anonymous]

Get carb dip....strip, dip, replace all rubber ('cept diaphram on slide, just DON"T DIP THAT)

[AOD]

if you're adjustment screw was way out of whack...that might be why the thing didn't want to idle.

like i suggested last night, try going 3-4 turns out and seeing how it runs.

~Adam