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Discussion Starter #1
I have a 1986 Honda Shadow VT500c. I noticed that the idle speed on my bike seems to be around 2000. I tried adjusting this with the idle screw but it was all the way out and not touching the throttle. I threaded the screw in and seemed to make my rpms jump up very high so I quickly undid the screw backing it all the way out. What could be causing this. Also I've noticed that when I shift to 1st gear from idle or 2nd it makes a audible clunk sound. It doesn't do this every time but pretty frequently. I will provide a pic of my rpms at idle.
 

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Is the choke moving freely? On these carbs "choke" is a bit of a misnomer, they actually use an enricher. The choke cable moves small pistons in enrichment ports in the carb. If one or both of these pistons arent fully closing it could cause a high idle situation
 

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Also could be your throttle cables. Make sure you have about 1/4 inch of play on your throttle.
 

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I tried adjusting this with the idle screw but it was all the way out and not touching the throttle. I threaded the screw in and seemed to make my rpms jump up very high so I quickly undid the screw backing it all the way out.
After re-reading your post, I realize my last reply was talking about the same thing. I've always called it the throttle stop but that's incorrect. Have you checked the A/F mixture screws on your carbs? They could be all out of wack. You'll want to turn them all the way in until they are lightly seated (don't go any further or you'll damage the needles) and then bring them out 2 to 2 and 1/2 turns and start there, or if you have a Haynes manual check what that says for your initial settings and then adjust from there.
 

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Discussion Starter #8
So after adjusting the left side choke I then moved on to the right side one. After unscrewing from the carbs I noticed it was missing the spring. Could this be the reason I am getting a high idle. My theory is that without the spring it is causing the valve to not fully close allowing air to get in.
 

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So after adjusting the left side choke I then moved on to the right side one. After unscrewing from the carbs I noticed it was missing the spring. Could this be the reason I am getting a high idle. My theory is that without the spring it is causing the valve to not fully close allowing air to get in.
That definitely makes sense. These bikes use an enricher as opposed to a typical choke. Instead of cutting off air it adds fuel. So it was probably stuck in the open position causing it to continue dumping extra fuel in one carb.

I was missing one of the springs and ended up just finding a spring in my tool box junk drawer that was enough of a match that it functions properly.
 

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Oh, and if you have an old spring, you can always take it to Ace Hardware and have an OLD GUY help you find a new spring that'll work. The kids have zero idea about recoil rates & stuff...usually.
 
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Big Shrek
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