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OK so I have a 98 xc 600 and all carbs ,needles, jets are all new n were set at dealer so my problem is its only backfires when choke is all the way down or off and it bogs on take off to and wet plugs ... But if I leave the choke on half way it doesn't backfire or bogs but I can flip choke off once I'm going and no problems at all ... Where do I start????

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Sounds like the idle jets are making it too lean. Replace or adjust them. If it has EFI, it can be fixed by changing the calibration map.

Posted on Dec 12, 2014

  • tony christenson
    tony christenson Dec 12, 2014

    how do u adjust the idle jets

  • digitalmoore Dec 12, 2014

    check that the clamp attaching the carby to the motor is tight and isnt allowing an air leak first. the mixture screw is on the lhs near where the bowl attaches, screw it out a half turn and see what happens. if it neither of those it might have the wrong needle shape installed, the dealer needs to fix it.

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Hi, Anonymous and the usual suspects are:
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Please rate this answer. Thanks kschomig!

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