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Idle Problem

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Old Feb 1, 2016 | 09:19 PM
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Default Idle Problem
I have 2003 Heritage Softail Classic that has had a CV Performance Tuner kit in it. It runs ok but more times than not after it is rode for awhile it starts to idle fast. An old biker friend of mine has said it is the thunder valve spring. I am not sure what that is. Also the vacumm slide and spring were replaced. Could this be the problem.
 
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Old Feb 2, 2016 | 11:45 AM
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I would start with checking for vacuum leaks first, where the intake seals up to the heads when the engine is hot.
 
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Old Feb 2, 2016 | 01:42 PM
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I have replaced the intake gaskets as well as the rubber boot then sprayed them with carb cleaner and WD-40. Couldn't tell any difference so I believe they are good. Also had a dealership look at it. All they did was to adjust the mixture screw but it made no difference.
 
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Old Feb 3, 2016 | 09:01 AM
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When you adjust the mixture screw in a turn and Out a turn does it make any difference ata all..?

And what color are your plugs?
 
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Old Feb 3, 2016 | 07:02 PM
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It doesn't really make a difference with the mixture screw. The plugs are a dark grey color, not white yet not wet either
 
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Old Feb 4, 2016 | 08:58 AM
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If turning the idle mixture screw in a full turn, then waite for an idle change, and then back Out one full turn (to its starting point) and then another full turn Out and that as well does nothing to the idle quality then I would say the carburetor needs a good cleaning and rebuild...
 
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Old Feb 4, 2016 | 05:31 PM
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Thank you very much 98hotrodfatboy. I have moved the screw back and forth quite a bit and you have just confirmed my thoughts. A rebuild is in the works
 
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Old Feb 5, 2016 | 07:29 AM
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Glad I could help...
 
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