carb idle screw

Cody hansen

New Member
Nov 29, 2017
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Los Angeles
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Hello everyone. Hope you all had a happy holidays. I know mine was good when I got my chinagirl up and running just in time for Christmas. But now I'm focused on making sure everything is running smoothly. I have no idea how to adjust the idle screw. Looked at a few videos online. No clue whether the screw should be in or out. Lol any and all tips are helpful. When I have some daylight I'll upload a picture of the carb. For now I jus have a finish pic.
Side topic*** how can i set my tank snug on my top bar without interrupting the function of my back brake. It tends to stick under the tank. For now I jus set my tank a slight angle to the right and the brake works fine but I don't like my tank on a slight angle. Thanks
 
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Greg58

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May 1, 2011
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First the idle screw is tapered to a point, screwing it in will raise the idle, out will lower it. From the picture it looks like you'll have to add spacers on each side of the cable to create a tunnel of sorts for the cable to go in. One thing that helped mine was to get the tank where I wanted it and filled the area on both sides of the frame bar with rtv after turning the bike upside down.
 
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crassius

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Sep 30, 2012
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skinny piece of RTV next to cable - double sided tape under & over PVC

or just run cable under frame thru tank studs
 

Cody hansen

New Member
Nov 29, 2017
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Los Angeles
Nice idea for the cables thanks. As for the idle screw YouTube videos have suggested that the idle be as low as possible without cutting off... Is that right?
 

crassius

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Sep 30, 2012
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expect the idle to change a bit between hot & cold motor - the diff will get less as motor runs in
 

allen standley

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Oct 22, 2011
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Bangor, Maine
crassius,
Or anyone else buying these for a while - quick thought occured reading this post. Has anyone else noticed in any of your newer kits, (talking NT carbs) seems the idle adj. needle is more pointed at the end than rounded over? and maybe a tiny bit shorter? I have for the past 4 kits purchased. Seems not a problem -just have to screw it in deeper compressing the spring almost max for a good idle adjust.
 
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crassius

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Sep 30, 2012
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USA
typically, idle screw all the way in means needle needs to be dropped a bit leaner

given a long screw and a file, one can easily make a new one with nice polished, rounded tip in 20 minutes or so (had to make one with thumbscrew end for a z-intake that left carb back against the seat post
 

Greg58

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May 1, 2011
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Newnan,Georgia U.S.A.
I have noticed some differences between carbs from several suppliers, the threaded part on the barrel that the screw goes in may be longer on some.