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I am tuning up the mountain bike I purchased in 1994, which has the old yellow Rockshox Quadra 21R front suspension fork. I have found a nice video on YouTube which shows how to service the suspension, and replace the elastomers, and also found an elastomer replacement kit for the fork at suspensionforkparts.net.

My concern is, when I unscrew the top plastic nut to remove the old elastomers, that I have found the old elastomers to be very brittle, several of them breaking into pieces upon removal, with brittle chunks still stuck within my fork. I can get the top-most units removed, but I know there is still at least one or two layers of elastomer in the bottom of the fork.

Does anyone have experience removing old brittle pieces of elastomer without damaging the tubes of the fork? My intuition says I should get in there with a long flathead screwdriver and a hammer, but I do not want to damage parts within the bottom of the fork that I cannot see. I also will need to access the very bottom of the fork with a long hex wrench when the elastomers are removed to fully disassemble and service the the bottom shafts. So, I am a bit worried that my screwdriver approach will jam the old elastomer pieces in the bottom of the fork, preventing access to the hex screw.

Thank you in advance for any tips you can offer on safely removing the old brittle elastomers.

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I've never dismantled a fork intending to reassemble it, but...

Could you use a J-end spoke or a knitting hook to pull the elastomer rather than pushing it?

You should be able to get plastic knitting hooks so the inner surfaces aren't scratched.

  • Care to explain the -1??? – Emyr Nov 12 '14 at 10:09
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    Apparently an accidental click - my bad. I can't reverse as voting is locked for me (too much time has passed). If you edit your answer, voting will be unlocked for me and I will correct the accidental down vote. – Rider_X Nov 12 '14 at 20:31
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The replacement elastomers I ordered from suspensionforkparts.net arrived and I replaced them this past weekend. Easy job, and the front suspension works like new!

enter image description here

  • This should have been edited into your previous post. Also, you may want to accept an answer. – Batman Dec 16 '14 at 19:46
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So this was helpful to me, but I had to use some different techniques. The elastomers weren't that bad, but the old lubricant was thick and sticky so everything was stuck.

I needed a really long lag bolt, LOTS of WD-40 to dissolve the old oil, and one of those grabby things. The grabby thing does not hold on to stuff very tightly at all, so I'd squirt some WD-40 in there, bang on it with the long bolt, and carefully grab the little plastic nub with the grabby thing and try to work it until it started to come out.

The long bolt of the right size (about twice the diameter of the nubs on the plastic pieces) worked really well to slip into the hole of the rubber elastomers, give it a couple of twists to screw it in tight, and the pull them out.

I'm posting pics of the tools I used, the elastomers pulled out, and the bike I'm working on.

enter image description here

,

  • I've got a soft spot for those '90s bonded aluminum ZX frames - your yellow one looks very nice! Thanks for the extensive photo details. – Armand Sep 5 '20 at 1:21
  • I'd never seen one before, but it was so pretty I had to buy. It was pretty cheap because everything on the bike was broken, including fork. Basically just bought it for the frame. Still trying to decide what kind of drive train to put on it. 3x8 like original? 2x10? Maybe 1x11 (probably not). Big project. – The Lizard Sep 6 '20 at 13:57
  • Still good deals to be had on mid-range 2x10 items. I'm habbing two ZX 7000s (not quite as light frame, as made with the 6000 series instead of 7000 series aluminum). If you go for external bearing BB, have your local shop "chase and face" the BB face and threads so the external BB bearings are seated flush and parallel on the frame. I also swapped out the canti brakes for V brakes (which require new brake levers as well). – Armand Sep 7 '20 at 3:30
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Thank you for your tip, Emyr.

I ended up using my screwdriver and hammer method to work around all of the brittle elastomer sections. However, at the bottom of the last section of elastomer was a round piece of plastic with a hole in it. I did just what you suggested to remove it -- I bent the end of an old spoke into a "J" shape, and pulled it out of the fork.

My new elastomers are coming in this weekend, and I look forward to repairing my front suspension. Thank you for the help.

Here's a photo of the old elastomers from the Rockshox Quadra 21R fork, now 20 years old! They are laid on the table with the botom of the fork toward the top. The small plastic ring you see is what I removed with the "J" shaped spoke.

Old elastomers

  • I know this is really old, but I'm in the same situation, but my old elastomers are not is as bad a shape. I've managed to remove several, but there are some of the plastic pieces with nubs way down in the fork. I'm not sure how a screwdrive and hammer would work, even if I had a screwdrive that long. I just don't see any way to grab the pieces left to pull them out. How did you manage it? – The Lizard Aug 31 '20 at 21:26
  • Wow, the internet is an amazing thing, isn't it? I forgot about this project, and recently upgraded to a newer bike, but rode this one through the beginning of 2019 with my replaced elastomers! – Ryan Sep 1 '20 at 22:04
  • @TheLizard -- Reading the above, I think what I did was take an old wire coat hanger. I cut it part way, and then used some pliers to bend a tiny "J" at the end. I then stuck the "J" down into the shock and used the little hook to try to catch and pull-up the pieces that were inside. You might need to try this, also while turning the bike/shocks upside down. If you have a rubber mallet, tapping the shocks while they are upside down might also help loosen up whatever remains on the inside. Good luck! – Ryan Sep 1 '20 at 22:06

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