High idle issue on CV carbs
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High idle issue on CV carbs

This is a discussion on High idle issue on CV carbs within the Technical forums, part of the Caferacer.net Forums category; Ok gang, I'm having some high idle issues on my 82' KZ440 with CV carbs. My idle was perfect until I took a quick run ...

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    Ews
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    High idle issue on CV carbs

    Ok gang, I'm having some high idle issues on my 82' KZ440 with CV carbs. My idle was perfect until I took a quick run up the Spiral Highway, when i got to the top I noticed my idle was high, around 5k rpm. When I finally got the chance to address it yesterday I thought I had found the culprit and made some adjustments. Started it up and let it get warm and idle was acceptable (approx 1k rpm). On my way to work this morning I again noticed the idle has crept up, by the time I parked it was idling at 4k. Not sure what to think, I know the idle adjustments are snug, not likely that it un-adjusted itself. I am wondering if it could be something like the return spring just isn't springy enough anymore? Any thoughts?

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    Senior Member woodsman's Avatar
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    Sticky cable.

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    Ews
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    Quote Originally Posted by woodsman View Post
    Sticky cable.
    I suppose that is possible, haven't replaced that yet. Did the clutch cable last year and the old one had a lot of rust in it, so throttle cable is a good idea to change even just because.
    Dream as if you live forever, Live as if you die today.~ James Dean

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    Senior Member Geeto67's Avatar
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    check for air leaks when warm as well - some parts don't leak when cold, but can introduce a leak as they warm up and expand.
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    Ews
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    Quote Originally Posted by Geeto67 View Post
    check for air leaks when warm as well - some parts don't leak when cold, but can introduce a leak as they warm up and expand.
    I always keep my eyes open for leaks, haven't seen any yet, but I will be looking a little closer.
    Dream as if you live forever, Live as if you die today.~ James Dean

    I feel the need, the need for speed.~ Mavrick (Tom Cruise before he was a big ol' bag of crazy)

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    Senior Member Geeto67's Avatar
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    Quote Originally Posted by Ews View Post
    I always keep my eyes open for leaks, haven't seen any yet, but I will be looking a little closer.

    how do you check for leaks? Smoke? carb cleaner?
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    Senior Member woodsman's Avatar
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    A light oil, I use sewing machine, and a fine oiling can. Disconnect the handlebar end and hold as vertical as possible, touch the tip of the oiler to the cable and you should slowly run down the cable and into the sheath. If that's the problem change the cable, where it's binding there's corrosion and the surface will be rough. Cables are metal on metal, you should lube them once in a while.

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    Ews
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    I went and re-re-adjusted my throttle cable position nuts, idle, etc... it's idling normal now. I will just have to wait and see if it creeps back up again. Inspected the throttle cable, no signs of rust or anything that would cause it to bind, moves freely within its shielding. I do however think I have a fouled plug now. Got caught in a monsoon on my way home from work Friday evening, thinking I somehow got some water sucked into the #1 cylinder. At this point I am putting it up for sale. I love the bike and it has been great for the last few years, but I need it as my daily and I dont have time to tear it down and fix everything properly, nor do I have time to constantly tweak and adjust things.
    Dream as if you live forever, Live as if you die today.~ James Dean

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    Senior Member Geeto67's Avatar
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    water in the cylinder (in small amounts) would clean and decarbonize it, not cause a plug to foul. Water shorting out a coil or an ignition trigger would do that though.
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    Ews
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    Quote Originally Posted by Geeto67 View Post
    water in the cylinder (in small amounts) would clean and decarbonize it, not cause a plug to foul. Water shorting out a coil or an ignition trigger would do that though.
    There was enough down poor that this is highly likely
    Dream as if you live forever, Live as if you die today.~ James Dean

    I feel the need, the need for speed.~ Mavrick (Tom Cruise before he was a big ol' bag of crazy)

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