Is my fork running low?

echowitch
echowitch Posts: 196
edited March 2014 in MTB workshop & tech
I have a Rock Shox Reba SL 29er 100mm White Front Fork

viewtopic.php?t=12909607&

It seems to me to be riding low. (Pics in the above link how it was 6 months+ ago, and the last pic shows it when it had the frame swapped over.

Is there a way to tell if it is low and any way to fix it short of sending it off for Service ?

The guidemarks on the fork itself are sat on the lower 30% mark even when I am not sat on it.

Comments

  • mcnultycop
    mcnultycop Posts: 2,143
    Have you put some air in it?
    Nerve AM 7.0
    Scandal
    Felt Roadie
  • echowitch
    echowitch Posts: 196
    Yep pumped it up to the stated pressure for my weight
  • cooldad
    cooldad Posts: 32,599
    So pump it up for the correct sag and ignore the tables.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • echowitch
    echowitch Posts: 196
    It just doesn't seem as high as it was. Just wondering what the best way to check it is correct. As it is a 100mm fork should the exposed stanchions be 100mm when there is no weight (i.e. no rider) on them ? Would that be the easiest way to check ?
  • The Rookie
    The Rookie Posts: 27,812
    A 100mm fork will have about 110-120mm of exposed stanchion so they don't bottom out on the seal.
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • echowitch
    echowitch Posts: 196
    Cheers :) I will have to break out the tape measure when I get home then :)
  • echowitch
    echowitch Posts: 196
    75 to 80mm in length :(

    And I bled all the air out and repumped it up again
  • neiltb
    neiltb Posts: 332
    my reba's have an upper and lower air reservoir, with a schraeder connection for each, I noticed this at one point, removed all air from both chambers and started again and got all my 120mm back.
    FCN 12
  • 97th choice
    97th choice Posts: 2,222
    If they are dual air then air in the negative chamber can suck them down but I think they are solo air?
    Too-ra-loo-ra, too-ra-loo-rye, aye

    Giant Trance
    Radon ZR 27.5 Race
    Btwin Alur700
    Merida CX500
  • echowitch
    echowitch Posts: 196
    Double checked (now I am back from snowboarding in France) and they are Single Air. I bled all of the air out again, pumped them up and down a couple of times and still the same thing when I readded air. I will take them to Evans which are my local Rock Shox point of contact and get them to take a look. Maybe they can suggest a quick fix or if they need to go off to SRAM for fixing.
  • The Northern Monkey
    The Northern Monkey Posts: 19,174
    When were they last serviced?
    Reba service is easy and can be done at home!
    Santa Cruz Butcher
  • echowitch
    echowitch Posts: 196
    Last year.....maybe 6 months ago with the lockout failed. I have noticed that the lockout isn't exactly working fantastically. :p

    Any guides anywhere on doing a Reba service ? Or is it better to get a tech to do it ?
  • cooldad
    cooldad Posts: 32,599
    Sram website - the technical section
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • echowitch
    echowitch Posts: 196
    Cheers :D
  • echowitch
    echowitch Posts: 196
    According to Evans it is possibly a seal on the negative air chamber. However the lockout isn't working again so I am trying to find out if I can get it fixed under warranty by SRAM at their service centre in Windsor. Fingers crossed. Bloody annoying though as this is the second problem with the fork in a year.

Categories