990 Mono Shock Rebound Adjuster

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by Hootowl, Mar 21, 2013.

  1. Hootowl

    Hootowl Long timer

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    The rebound adjusting screw on my 07 is not working. It's possible to turn it either direction endlessly. I can feel the detents but it never reaches a stop.
    I'd like to have the needed parts in hand when I take it to a local shop for basic service and repair/replacement of the screw so that my 990 is not ride-able for as short a time as possible. I assume its not something I can do at home.

    My question is: would I likely be covered if I ordered part number 50180434S (fiche here: http://partsfinder.onlinemicrofiche.com/ktmtwins/KTM_OEM/KTMDB.asp?Type=13&A=361&B=7)

    Richard
    #1
  2. Peanuts

    Peanuts Long timer

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    The adjusting screw has like an hourglass shape that works like a ramp for the damping adjustment. It seizes inside the shock and if you try to turn the adjuster it snaps at the narrow part.

    Replacement is best left to someone familiar with WP shocks, they will probably have the part as it is a common problem.

    Most people just live with the fact that they cannot adjust the damping ;)
    #2
  3. dmn0507

    dmn0507 Been here awhile

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    mine was seized and needed an extractor to remove the stuck part.
    If you can live with the current rebound setting, just wait till your shock needs a rebuild.
    #3
  4. crazybrit

    crazybrit Long timer

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    Not that this helps OP but every oil change, mine gets a squirt of WD40 and backed down and then reset.
    #4
  5. Zuber

    Zuber Zoob

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    Do you pull the rubber plug and spray into the cavity? Or do you just spray around the screw head?

    WD40 helps, but an anti-corrosion would be better.

    I fix these broken screws once a month, you must release the pressure, unscrew the guide bushing, remove the broken parts, drill the screw and use a GOOD screw extractor and lots of heat to remove the broken part. It is very tough to drill, you are trying to start the bit on the point of a cone. It takes a drill bushing to protect the shock body. New parts, re-charge the shock.

    If you have more than one year and 15k miles on the bike, it is time to service the shock. Be sure they pull this adjuster screw out and grease it with an anti-corrosive grease. This first service is most important. The second service is not.
    #5
  6. crazybrit

    crazybrit Long timer

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    I usually just give it a long spray around the screw head. Leave for 5 mins. Back it all the way down. Do the oil change. Give it another spray and reset to old value.

    I'm all ears if the remove plug is better way? Agree, removal and anti seize sounds like a sound idea.
    #6
  7. HeatXfer

    HeatXfer Bad knees

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    WD-40 was never meant to be a lubricant - it was designed as a moisture dispersant, hence the "WD". It's far too light for any load protection (although that screw doesn't really see a 'load') has poor corrosion resistance, and rapidly oxidizes to form a sickly yellow varnish.
    I use LPS2 for any small mechanism: it leaves a light oily coating and won't gum-up.

    /2ยข


    #7
  8. Hootowl

    Hootowl Long timer

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    #8
  9. TcRulz

    TcRulz Been here awhile

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    Hi guys and thanks for the wisdom. Just making sure I understand this right. It's alright to take the screw out and coat with anti-seize and nothing bad will happen. Please reassure me either way (cos I'm scared:rofl)
    #9
  10. AdvRonski

    AdvRonski They call me......Ronski

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    You must release all of the shock's nitrogen pressure to remove the adjuster screw, so you may as well have it serviced by a pro.
    #10