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Won't Idle

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Old Apr 30, 2020 | 03:49 PM
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Default Won't Idle

Setup:
  • 01 Sporty XL1200C Evo
  • Stage 1 Arlen Ness Big Sucker intake (newly installed)

This post is an extension of a previous thread:
https://www.hdforums.com/forum/sport...take-leak.html

Before I had an intake leak and this appears to be fixed.
Current situation:
  • Bike starts and idles (seemingly) smooth
  • After 30 seconds the bike dies
This is with choke all the way out. Whenever I twist the throttle while idling, it bogs down.
There does not seem to be any fuel coming out of the AP nozzle when twisting the throttle.

The carb has been disassembled and cleaned. Everything seems to be working properly. Has new AP diaphragm.

Here is a video of the issue:
 

Last edited by Ryant.glasgow; Apr 30, 2020 at 06:00 PM.
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Old Apr 30, 2020 | 05:11 PM
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If you aren't getting any gas coming out of the accelerator pump nozzle when you twist the throttle your carb is not clean. Squirting some carb cleaner in a carb is not cleaning it. You have to completely disassemble it and get all the little holes clean

Or you could have a torn accelerator pump diaphragm, but if you cleaned the carb properly you should know that.
 
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Old Apr 30, 2020 | 05:58 PM
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Originally Posted by VAFish
If you aren't getting any gas coming out of the accelerator pump nozzle when you twist the throttle your carb is not clean. Squirting some carb cleaner in a carb is not cleaning it. You have to completely disassemble it and get all the little holes clean

Or you could have a torn accelerator pump diaphragm, but if you cleaned the carb properly you should know that.

I appreciate you assuming I just sprayed carb cleaner in it and called it "clean". But I have completely disassembled, inspected and cleaned every component. The AP diaphram is brand new, just replaced it.

Helpful suggestions are welcome. Thanks
 

Last edited by Ryant.glasgow; Apr 30, 2020 at 06:02 PM.
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Old Apr 30, 2020 | 05:59 PM
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Originally Posted by Ryant.glasgow
I appreciate you assuming I just sprayed carb cleaner in it and called it "clean". But I have completely disassembled, inspected and cleaned every component. I the AP diaphram is brand new, just replaced it.

Helpful suggestions are welcome. Thanks

Something is blocking the AP then it is not clean.
 
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Old Apr 30, 2020 | 06:07 PM
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You may think you have the carb clean, but it is not. I've had to pull them apart 3 times thinking I cleaned them every time.

Gas should be coming out of the accelerator pump nozzle when you twist the throttle, but it's not, that is why it is bogging down and dying.

You either didn't clean it right, or since you say you have a new diaphragm, you didn't reassemble it properly. Go back take the carb apart and do it again.
 
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Old Apr 30, 2020 | 06:19 PM
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Originally Posted by VAFish
You may think you have the carb clean, but it is not. I've had to pull them apart 3 times thinking I cleaned them every time.

Gas should be coming out of the accelerator pump nozzle when you twist the throttle, but it's not, that is why it is bogging down and dying.

You either didn't clean it right, or since you say you have a new diaphragm, you didn't reassemble it properly. Go back take the carb apart and do it again.
I've done it multiple times, which is why i was thinking it might be something else.
 
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Old Apr 30, 2020 | 06:36 PM
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Originally Posted by Ryant.glasgow
I've done it multiple times, which is why i was thinking it might be something else.

You gotta get gas coming out of the AP. If that isn't your entire problem it is a significantly contributing factor.

There isn't that much else there, you are getting gas to the motor because the bike runs and starts.

Make sure the little linkages are hooked up right and the plunger is being pushed when you twist the throttle.

If they are, then, Pull the cover off the AP use the thin red tip with your carb cleaner spray and make sure you can spray through the AP nozzle. Also make sure the passage is clean and you are getting gas into the AP diaphragm.

 
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Old Apr 30, 2020 | 06:43 PM
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Originally Posted by VAFish
You gotta get gas coming out of the AP. If that isn't your entire problem it is a significantly contributing factor.

There isn't that much else there, you are getting gas to the motor because the bike runs and starts.

Make sure the little linkages are hooked up right and the plunger is being pushed when you twist the throttle.

If they are, then, Pull the cover off the AP use the thin red tip with your carb cleaner spray and make sure you can spray through the AP nozzle. Also make sure the passage is clean and you are getting gas into the AP diaphragm.

Alright thanks for the help. I'm gonna take it back off and test out the AC pump again. I tested after I first took it apart, and it was working. Is it possible that the bowl isn't filling for some reason?
 
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Old May 1, 2020 | 09:05 AM
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Originally Posted by Ryant.glasgow
Alright thanks for the help. I'm gonna take it back off and test out the AC pump again. I tested after I first took it apart, and it was working. Is it possible that the bowl isn't filling for some reason?
A clogged AP nozzle is probably more likely. You can pull it off and spray directly into it. I believe they can be replaced, either at HD or CV Performance.

John
 
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Old May 1, 2020 | 01:13 PM
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Turns out it was my problem. Took the bowl off again and tested the AP, again, and it was working perfectly. Not much gas in the bowl, so it wasn't getting to the inlet for the AP. Tested my pitcock and it was only letting a small amount of fuel through. Swapped it out and it runs great now!
 
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