Exhaust servo not fully closing valve/flap

Discussion in 'Maintenance' started by Keef690, Feb 10, 2024.

  1. Keef690

    Keef690 New Member

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    Hi all, newbie here.

    I have trawled this and other sites for an answer, but most people say to remove the cable and have the flap open all the time. I would like the bike to be as it is intended, so quiet on start up and then have the valve opening at 4-5,000 ish rpm. I have removed the cover under the seat, turned the servo so the flap is fully closed, but then after a ride or two it is not closing fully again. How can I fix this? Would another servo help? Can I check how it is operating somehow? Would a new cable help? Is the cable adjustable? Can it be reset?

    Any help would be appreciated.
     
  2. Muffking

    Muffking God Like

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    What year?
    They are not adjustable and AFAIK you can't check to hem static.
    I would either try another servo or get it on a rolling road where you can check it, assuming that the exhaust valve moves freely.
     
  3. Keef690

    Keef690 New Member

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    Oops RR8 2008. Flap moves freely
     
  4. bonjo

    bonjo Active Member

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    do you havbe the pulley in the reight position with the engine off?
    the service manual shows the poisition of the pulley
     
  5. Keef690

    Keef690 New Member

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    I will check the pulley position at the weekend, but I thought I had checked before and then it was fine for a couple of rides.
     
  6. Jay Floyd

    Jay Floyd Active Member

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    Has the cable stretched? or can it be adjusted?
     
  7. Keef690

    Keef690 New Member

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    Exactly, can it? Anyone?
     
  8. keitheg6

    keitheg6 New Member

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    Possible the cable has stretched but doubtful they normally rot away before that happens.

    Is it on the right notch on the servo? the adjustment should be on the flap side of the cable. If you move the servo out of position with the seat off and ignition off, when you switch on the ignition the servo should correct its position fully open and to fully the closed position ( stepper motor so no actual feed back loop). Check that and see if the flap is actually fully closed before adjusting. Remember fully open is fail position so when closed there should always be tension on the cable.
     
  9. Keef690

    Keef690 New Member

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    Update for anyone that comes across this. Just a stretched cable,no surprise after 68,000 miles and it is adjustable at the exhaust end. Remove the cable from the servo, undo the 14mm nut on the exhaust and turn the threaded part clockwise. Then do up the nut and re-attached the cable. It took a couple of attempts to get it spot on so trial and error reattaching, turning ignition on and feeling if the valve is closed.
    Thanks for the ideas guys
     
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