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Discussion Starter · #1 ·
88 twin cam carburetor motor. My problem is when motor has been running for a bit and I stop at a light the motor will rev up to 14-1500 rpm. Sometimes it will go down to 8-9 hundred. Had a stock carp then an SnS carb , changed jets, gaskets, and just about everything I can do and it will continue to do it!
so wondering if someone might know what is going on with it.
 

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Not sure what year your bike is, but it sounds like a MM EFI issue that is pretty common, but you said you have a fish instead of EFI.

Why would you change the jets for an idle issue? If this is "just about everything" you can do, that might limit the range of usable answers. Did you really change the carb and still have this same issue before and after the carb change?
 

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Discussion Starter · #5 ·
Not sure what year your bike is, but it sounds like a MM EFI issue that is pretty common, but you said you have a fish instead of EFI.

Why would you change the jets for an idle issue? If this is "just about everything" you can do, that might limit the range of usable answers. Did you really change the carb and still have this same issue before and after the carb change?
i changed carbs, jets, idle size , intake gaskets, like i said everything i can think of has been dealt with at least twice to make sure i didnt mess something up the first time.
 

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Discussion Starter · #6 ·
What have you eliminated? Have you looked at anything?

Intake leak is where I would start...and most likely the issue.
like I said i've replaced or changed everything from the air cleaner to the intake gaskets at least one.
i changed carbs, jets, idle size , intake gaskets, like i said everything i can think of has been dealt with at least twice to make sure i didnt mess something up the first time.
its a 2005 classic
 

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Could the enrichener blade be moving?
 

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Find a book and adjust your throttle and idle cables. One or both of them could be causing this issue. Any little movement of the fork can cause your idle to go up or down.
 
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Which S&S carb did you put on? Was it a new carb? What tuning procedure did you follow when you installed it?

You say you changed jets. Was that with the S&S? Did you change them as part of a tuning procedure or just random changes hoping for a good result?
 

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Find a book and adjust your throttle and idle cables. One or both of them could be causing this issue. Any little movement of the fork can cause your idle to go up or down.
Yes, throttle cable seems like a likely suspect since the carb change seemed to make no difference.

So, the question is what happened before this problem started?
 

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2004 FLSTCI, 1993 FXDL
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Discussion Starter · #14 ·
Which S&S carb did you put on? Was it a new carb? What tuning procedure did you follow when you installed it?

You say you changed jets. Was that with the S&S? Did you change them as part of a tuning procedure or just random changes hoping for a good result?
Super E read instructions and called them. Didn’t have an answer. So just trying different jets and so worth to see if would make a difference. So far nothing has worked. Every once in a while it will drop on its own and that just makes it all the more strange
 

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Most of these guys are smarter than I when it comes to troubleshooting, but it seems like you've elminated possible fuel issues. I'd probably be interested in testing the speed sensor. A faulty speed sensor can cause strange idle symptoms. In my experience your speedometer may also be off and it can issues with turn signal canceling as well. I don't think every symptom would necessarily be present.
 
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