Adjusting idle screw on Kymco scooter/keihin carb?

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Adjusting idle screw on Kymco scooter/keihin carb? by: stephm - Sept 3, 2013 21:13:53 GMT -5

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Post by stephm on Sept 3, 2013 21:13:53 GMT -5

I'd like to start by telling you all I know nothing about scooter engines/repairs.

My new Kymco Sting 50 keeps dying when it is in idle. After doing some research online, I think what I am supposed to do is to adjust the idle screw on the carb. I located the carb (after a little bit of difficulty), but I have NO idea which screw to adjust and how to adjust it. I can see on there that it is a Keihin carb and I found this on their website explainin which screw it is, but I don't think mine is exactly like the diagram so I am not sure what to do...

keihincarbs.com/tips/gate.html

Here are some pictures I took of the carb: imgur.com/a/yY2RL

Can someone please help?

Last Edit: Sept 3, 2013 21:23:27 GMT -5 by stephm

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Adjusting idle screw on Kymco scooter/keihin carb? by: skuttadawg - Sept 4, 2013 1:30:34 GMT -5

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Post by skuttadawg on Sept 4, 2013 1:30:34 GMT -5

Read this itistheride.boards.net/index.cgi?board=tt&action=display&thread=53

Mine idled weird at times and worse with a BBK but going from a 40 idle jet to a 45 and now it purrs

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Adjusting idle screw on Kymco scooter/keihin carb? by: SylvreKat - Sept 4, 2013 5:43:51 GMT -5

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Post by SylvreKat on Sept 4, 2013 5:43:51 GMT -5

My suggestion since it sounds like you don't have the tools or knowledge, and since it's new--take it back to the dealer and have them adjust it. Should be part of the new purchase to get it running correctly.

And ask them to show you what to do, so you can learn.

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sailracer PM sailracer sailracer's Posts sailracer's Threads Senior Rider Currently Offline My other favorite ride Posts: 1,240 Likes: 8 Joined: May 24, 2013 10:27:25 GMT -5	Adjusting idle screw on Kymco scooter/keihin carb? by: sailracer - Sept 4, 2013 6:56:29 GMT -5 Reply Quote Select Post Deselect Post Link to Post Member Give Gift Back to Top Post by sailracer on Sept 4, 2013 6:56:29 GMT -5 just follow the throttle cable. rule-of-thumb is, it'sthe closest screw to where it meets the carb.
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Adjusting idle screw on Kymco scooter/keihin carb? by: stephm - Sept 10, 2013 8:36:46 GMT -5

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Post by stephm on Sept 10, 2013 8:36:46 GMT -5

I can't take it back to the dealer, they're out of state. I adjusted the top screw in that picture. It no longer dies in throttle, but now it dies when I give it gas. Idk what to do. The dealer isn't answering any of my messages

stephm PM stephm stephm's Posts stephm's Threads New Rider Currently Offline Posts: 3 Likes: 0 Joined: Sept 3, 2013 21:07:30 GMT -5	Adjusting idle screw on Kymco scooter/keihin carb? by: stephm - Sept 10, 2013 8:37:31 GMT -5 Reply Quote Select Post Deselect Post Link to Post Member Give Gift Back to Top Post by stephm on Sept 10, 2013 8:37:31 GMT -5 I have NO idea what a throttle cable is

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Adjusting idle screw on Kymco scooter/keihin carb? by: JerryScript - Sept 13, 2013 2:08:19 GMT -5

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Post by JerryScript on Sept 13, 2013 2:08:19 GMT -5

The throttle is on the other side of the carb from the side you are showing in your pictures. It has a screw with a spring around it, that is the screw you need to adjust. Here is a picture of the other side of a Keihin carb, the throttle cable comes down along the left of the carb and then through the holding bracket along the lower portion of the picture, the idle adjusting screw you are looking for is the brass one in the lower right of the picture: