Thursday, 21 February 2013

Workshop: Fixing 55/33 and DJ 'R' cartridge forks


The 2008/9 R system caused many problems for the 55, 33 and DJ fork, the cartridge was a bought-in sealed item that was gas charged. The problem with was that the sealing was relatively poor and the cartridge could suck in oil from the outer leg, this overfilled the damper and created hydraulic lock. The fork became very hard and suffered from a loss of travel.
The good news is that the fork can be fixed relatively inexpensively (if out of warranty). All replacement cartridges are converted to open bath, so when installed, fixes the fork 100% with vastly improved performance. The open bath cartridge differs via the flow holes at the top and bottom of the cartridge.

Part numbers:
Y703897 – fits 33 R/DJ 1/ 2 2008/9
Y703898>A – fits 2008 Z1 SPORT/55 R

Once installed put the following quantity oil (SAE 7.5W) into the leg:
DJ1 – 150 cc
DJ2 – 190 cc
55R – 160 cc

Put air on the other side so to find the best balance for the rider. Suggested range for model fork:
DJ1 – DJ2:  2÷5 BAR
55R : 2 ÷ 3.5 BAR
Push up/down the fork until when the fork works correctly.


11 comments:

  1. Hello and thanks for the information. I have a 33R on my 2009 Giant Trance x4, I would like to perform this modification to my forks. I noticed there is no oil/air psi recommendation in your post for the 33r. Also, where can I purchase the parts described in the post? Thanks

    ReplyDelete
  2. Is the Y703898>A cartridge a replacement or an improved upgraded cartridge on the standard cartridge for the 2008 55r? Is it still a Sr Suntour cartridge?

    What other fork cartridges and years (with extras, caps, etc) are compatible with the 2008 55r?

    ReplyDelete
  3. And if my forks only compress 2 1/2 " does that mean this has happened and now I have to drill the holes?

    ReplyDelete
    Replies
    1. yes, you have hydraulic lock and you will need a replacement cartridge. Because of the internal pressures that are now inside the damper we do not recommend modifying the existing damper.

      Delete
  4. Can anyone link a replacement open bath cartridge for a 55 r bomber hydraulic locked.. cheers guys

    ReplyDelete
  5. Performing this mod soon, ill let u know if a part twangs and blinds me, or should i say ill get my gf to type it

    ReplyDelete
  6. Steve what year is your fork . Can you do anything to make 2014 55r better in anyway ?

    ReplyDelete
  7. Steve what year is your fork . Can you do anything to make 2014 55r better in anyway ?

    ReplyDelete
  8. I have the 2014 model that is sticky on the rebound could this be due to the damper or the seals somewhere in the fork, I have serviced them and cant find a solution.

    ReplyDelete
    Replies
    1. its probably a basic service issue rather than damper issue. A good clean and fresh oil will work wonders!

      Delete