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  1. #21
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    Thanks Charles. Unfortunately these pods are the only filters that came with the bike. The stock air box was long gone. So we'd have to buy a stock air box to get that baseline (believe me, I'm tempted!).

    If I could narrow down that this issue is indicating A) starved for fuel, B) too much fuel or C) electrical - we would be in a much better place. The fact that the bike has pods (most bikes run leaner) and no carbon/soot deposits on the plugs is in line with my logic based on other bikes with pod/airbox swap. But then again, these carbs seem to be laughing at my logic

    I would like to know some places to look for vacuum leaks like Phreak suggested. There may be some areas I have not addressed??? Also, I will have the carbs off again to see if we can get the tiny ports any cleaner with Phreak's tricks to blow them out.

    Thanks for the help.

  2. #22
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    Ok folks, here's the latest.

    I was able to test the pins #9/5 with the multimeter again - this time on AC volts. Number that came back was about 90v. Not sure if that's telling or not - not sure what a healthy measurement would be.

    The big news came when we took the carbs back off the bike, quadruple checked the tiny port holes that travel from the idle jet towers through to the throat of the carbs. All showed clean, with clear passage of air being felt distinctly from the 2 smallest holes behind the butterfly. Both holes in both carbs seemed clean. The air/fuel screw passage was already fine.

    I had purchased the rubber plugs that insert into the idle jet towers because they had been missing, but when we thought back to our initial testing - all the best results seemed to have been without these plugs. We decided to test the bike with the 90/120 jets, clean passages, and no rubber plugs. The issue was gone immediately. While the tuning could be a bit better, at this stage it seems that a slightly larger jet could do the trick. Air/fuel mix screw helped to a point, and then we ran out of comfortable adjustment room.

    So this doesn't sit well with me - getting the right result from the wrong reason... But at this point - it seems like it's worth trying under load. The irony that we finally get the bike fat a place woth road testing again during a snowstorm is not lost on us

    I'll update when I get a chance to fire her up on the road...

  3. #23
    Super Moderator CXPHREAK's Avatar
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    Is there a chance that the small drilling between the idle and primary jet towers is blocked and with the plug fitted there is no fuel supply to the idle jet.?

    Not one I've run across but it's the best I can make of your situation.
    Rebuilding Handlebar Switches

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    GET A MULTIMETER RTFM I am a CX500. If you maintain me I will run forever.

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  5. #24
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    Thanks for all your help CXPHREAK.

    It definitely passes air and carb spray when were cleaning them. I can check again when the new jets arrive - I'll just remove the carbs to install them instead of doing it on the bike. For now it's nice to have seen some progress, but of course "fixing" something by doing the wrong thing is never good

  6. #25
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    Hello ...new guy to the thread and first post on the forum ...I have owned CX500's years ago but just got back in with a 81 GL500... I just fixed a stumbling problem with the help of this forum and it turned out to be the spark plug resistor in combination with the resistor spark plug ...put an aluminum plug in the cap and solved the problem ...only problem left is an idle problem after coming to a stop . The engine runs on as high as 3K for a few seconds before returning to idle . I have cleaned the carbs numerous times but I may be missing something ? The boots are OK and checked with ether with the engine running .I'm looking for an area specific location in the carb I may have overlooked ...Thanks in advance ...great forum !...... Erwin Tennessee

  7. #26
    Administrator ChopperCharles's Avatar
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    If you're getting high-revving like that, you have an air leak between the carbs and the engine block. For that symptom, there is no other cause.

    Charles.
    Visit my Blog: Modified Motorcycles By ChopperCharles at http://choppercharles.com

  8. #27
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    The plug caps/wires on this bike measured within spec. So I think I'm ok on that front. But glad you figured it out for the GL.

    Sounds like hanging idle due to lean condition - but also sounds like you tried to spray around the boots to determine the cause. Do you have stock airbox?

    As these guys have mentioned: thoroughly cleaning the carbs seems like only a precursor to cleaning them again....and again....and...

  9. #28
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    Quote Originally Posted by ChopperCharles View Post
    If you're getting high-revving like that, you have an air leak between the carbs and the engine block. For that symptom, there is no other cause.

    Charles.
    Charles , thanks for the advice and I'll look a little closer . I did spray ether where the boots connect to the heads and got no change . Possible cracked head or valve problem ?. no visible leaks and no contamination in oil or water .....24K on the odometer . seems to be running more erratic now and does cough at 5 to 6k on occasion ...Cam chain ? I will test the ignition with an ohmmeter again before I go any further . Seems more like an intermittent electrical problem with the lean mixture combo ? I do have a spare carb that I can try also ....One problem at a time ...patience and persistence wins in the end ...I hope...This may take a while before I find anything and I'll let you know .

  10. #29
    Administrator ChopperCharles's Avatar
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    Spray where the carbs connect to the boots too. And spray the boots themselves. Cam chain has no bearing on this problem. All a bad cam chain will do is grind away at the engine case on the inside. It won't effect running to an appreciable degree. Cracked head will result in coolant in oil, or exhaust gases blowing through coolant and causing rapid over-heating. I've never seen a cracked valve on these engines, and it wouldn't result in high-revving anyways. Recommend you replace boots, replace o-rings in boots, and replace clamps on boots. If that doesn't fix it, you have a problem with the carbs themselves.

    Charles.
    Visit my Blog: Modified Motorcycles By ChopperCharles at http://choppercharles.com

  11. #30
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    David silver spares has a location here in the states now - they sell replacement boots and o-rings for a reasonable price. Almost worth it to rule out the issue.

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