Bike idling way too high after float adjustment

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sammydogjj
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Bike idling way too high after float adjustment

Post by sammydogjj »

I decided to go ahead and try adjusting my floats instead of rebuilding. It used to pour gas out and now it doesn't, but it idles way too high. Boots are snug on the carb, pic attached. The only time it doesn't idle too high is with the choke on. What do I do? What did I do wrong? Please help. Image


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Re: Bike idling way too high after float adjustment

Post by sammydogjj »

I didn't even clean it other than recleaning the float needle seat. I adjusted the floats and sometimes the gas line from gas tank bubbles instead of a constant flow like it used to. What is wrong?


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Bike idling way too high after float adjustment

Post by kx200 »

How far out is your idle screw?
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Re: Bike idling way too high after float adjustment

Post by sammydogjj »

kx200 wrote:How far out is your idle screw?
It was out a couple turns, but I just reset it to the 1.5 turns and adjusted from there. It didn't seem to help much, I just don't see why it would do this suddenly. All I did was change the float height, could I have over adjusted it? It was overflowing so I adjusted it to where it closes off earlier.


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Bike idling way too high after float adjustment

Post by Alectravis »

I had this same problem after I rebuilt my kdx, I would like to give you the exact reason, but I have no clue. after i had this problem I pulled it apart and replaced my head gasket and my reed cage gasket and checked everything over. Seems to be okay now. But I'm guessing it has something to do with that area between the cylinder and carb (if the idle screw does nothing.)
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Re: Bike idling way too high after float adjustment

Post by sammydogjj »

Alectravis wrote:I had this same problem after I rebuilt my kdx, I would like to give you the exact reason, but I have no clue. after i had this problem I pulled it apart and replaced my head gasket and my reed cage gasket and checked everything over. Seems to be okay now. But I'm guessing it has something to do with that area between the cylinder and carb (if the idle screw does nothing.)
The idle screw helps, but not much. If I screw it around 3-4 turns out it's about like it normally is. Could I have just over adjusted the floats?



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Re: Bike idling way too high after float adjustment

Post by ohgood »

sammydogjj wrote:
Alectravis wrote:I had this same problem after I rebuilt my kdx, I would like to give you the exact reason, but I have no clue. after i had this problem I pulled it apart and replaced my head gasket and my reed cage gasket and checked everything over. Seems to be okay now. But I'm guessing it has something to do with that area between the cylinder and carb (if the idle screw does nothing.)
The idle screw helps, but not much. If I screw it around 3-4 turns out it's about like it normally is. Could I have just over adjusted the floats?



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if you adjusted the float too lean, it would cough back bubbles (possibly) and make the idle faster, yes
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Re: Bike idling way too high after float adjustment

Post by sammydogjj »

ohgood wrote:
sammydogjj wrote:
Alectravis wrote:I had this same problem after I rebuilt my kdx, I would like to give you the exact reason, but I have no clue. after i had this problem I pulled it apart and replaced my head gasket and my reed cage gasket and checked everything over. Seems to be okay now. But I'm guessing it has something to do with that area between the cylinder and carb (if the idle screw does nothing.)
The idle screw helps, but not much. If I screw it around 3-4 turns out it's about like it normally is. Could I have just over adjusted the floats?



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if you adjusted the float too lean, it would cough back bubbles (possibly) and make the idle faster, yes
Too lean as in it shuts off earlier or overflows? It was overflowing so I made it close off earlier, and I have seen back bubbling (which I've never seen before) while it idles high. So a quick float adjust seems like it COULD help?


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Re: Bike idling way too high after float adjustment

Post by Tedh98 »

I would readjust the float so the fuel level is higher in the bowl and see if the high idle persists.

Or maybe the throttle cable got hung up while you were working on the carb and it isnt allowing the slide to close?
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Re: Bike idling way too high after float adjustment

Post by sammydogjj »

Tedh98 wrote:I would readjust the float so the fuel level is higher in the bowl and see if the high idle persists.

Or maybe the throttle cable got hung up while you were working on the carb and it isnt allowing the slide to close?
It could be a combination of either, that's what I was thinking. May as well break it open and rebuild it, because I have the parts. While I'm in there I'll adjust the floats a little and make sure when I reinstall the throttle tube it isn't hung up. For now I just have the idle screw around 4 turns out and it runs fine, but that's not a permanent fix.


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Bike idling way too high after float adjustment

Post by canamfan »

A quick way to check float height is to take off the float bowl, attach a longer fuel line to the carb. Put the end of the fuel line in your mouth (your going to blow thru it) hold the carb up where you can see the float easily. Let the float hang down, as you start to blow push the float up slowly. It should shut off the airflow when the float is parallel to the carb body gasket surface. Adjust accordingly and if it wont shut off you know you have a leaky shut off valve.
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Re: Bike idling way too high after float adjustment

Post by sammydogjj »

canamfan wrote:A quick way to check float height is to take off the float bowl, attach a longer fuel line to the carb. Put the end of the fuel line in your mouth (your going to blow thru it) hold the carb up where you can see the float easily. Let the float hang down, as you start to blow push the float up slowly. It should shut off the airflow when the float is parallel to the carb body gasket surface. Adjust accordingly and if it wont shut off you know you have a leaky shut off valve.
Thanks!


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Re: Bike idling way too high after float adjustment

Post by Jaguar »

twist the throttle and see if there is any play there. If not then most probably the cable didn't seat completely into its holder on the top of the carb which is causing the slide to be kept a bit open. If there's no play and the cable is seated correctly then just adjust the cable slack at the carb or at the throttle.
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Re: Bike idling way too high after float adjustment

Post by Slick_Nick »

Your throttle stop screw looks like it's in WAAAAAAAYYY too far.
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Re: Bike idling way too high after float adjustment

Post by Julien D »

Yes, it sounds like you are mistaking the air mixture screw with the idle screw.
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Re: Bike idling way too high after float adjustment

Post by G22inSC »

sammydogjj wrote:
kx200 wrote:How far out is your idle screw?
It was out a couple turns, but I just reset it to the 1.5 turns and adjusted from there.


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