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  1. #1
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    Lyrik RC2 DH Solo Air sometimes not fully extending

    This fork came on my SC Butcher which I bought about 9 months ago. Twice now in the past 3 weeks it won't fully extend on it's own (once was when I took it off the bike rack to start a ride, the 2nd time was while actually riding). I can easily push down on the crown and extend to full travel. Both times afterwards it rode fine.

    I'm wondering if this is the sign of a seal starting to fail? Anyone familiar with this issue?

  2. #2
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    Interested in this thread. I have the same thing happen to mine. It did it new and continues to do it many hours later. In my case it is about 5-7 mm worth. I should also mention this is in the 170mm mode. I have never had it or used it in the 160mm mode.

  3. #3
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    mine is the same, I found the problem since I bought it brand new, and I took it to service centre immediately and they said it`s normal, I am still rocking it right now without any problem. It still cant extend completely on it`s own, but who care.

  4. #4
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    I had the same problem with my 2009 Boxxer WC when I first got it. It turned out that when the fork was assembled it was partially depressed leading to create negative pressure on the compression side when the fork tried to return to full travel.

    The negative pressure ends up working similar to an air spring but has the reverse effect in that it will cause the fork to compress insead of extending completely upward due to the positive air spring in the other leg.

    Essentially what has to be done is that you remove the lowers (you don't need to remove the air spring) and do the partial service where you remove the damper oil. The trick is to"burp" the compression side when putting things back together to make sure that there is no negative pressure within the compression leg of the fork.

    If you do a quick search for "burping Boxxers" I'm sure you will find a better explanation. It really ended up being a balance between how much air I burped out of the compression side before re-assembly and how much travel I could get before the stanchions got pulled down again. If I burped too little air it felt like there was too much oil on the damper side and too much and the fork got pulled down.

    Edit: Take a quick read through this it sounds like the same issue to me:

    09 Red Boxxer Problems: Boxxer Guru's Please

  5. #5
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    I called RockShox (here in the US). They will need me to take to my shop for troubleshooting to verify the problem, but guessed it may have a defective air cartridge.

    So I'll know more once I take it in.

    @ Canadaguy - I have the solo air, so no negative air adjustment (which is sounds like the boxxer has) - I'd guess it's somehow contained in the air cartridge in the left leg.

  6. #6
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    Ah, OK. I see what you're saying now. I'll have to decide whether to let the shop give it a shot, or just try it out myself. It's still under warranty, so will probably let the shop work it out.

    Was you problem an on-again/off-again problem like mine (so far, has only happened twice since I got the fork last June)?

    I'll read through the thread you listed.

  7. #7
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    kbfalken, no the Boxxer is also solo air. The point I was trying to make is that when some forks are assembled the push rods inside the stanchions are somewhat depressed on the compression side. This in turn will "act" like a negative spring because air has been pushed out of that leg prior to sealing it with the compression damper. What results is that the compression side can't return to full extension because of the negative pressure created pulling the whole fork down.

    When I pulled up on my fork it would go to full travel, but then get pulled back down on its own due to the negative pressure. If you have ever put your finger on the end of an oil syringe and tried to pull the pluger up it wont go since you are creating a vacuum... same idea.

    Hopefully that made more sense. Rockshox also told me I had a defective air catridge but I didn't believe them. I pulled everything apart mostly out of curiosity and it turned out it had nothing to do with the spring side whatsoever.

    The fact that your fork hasn't done this since new means that this may not be the case. I would still try removing the compression damper then pulling up on the fork. If it sucks back down without the damper in place then it may be the spring side.

    Good luck sorting it out.

  8. #8
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    I have two soloair RC forks & they both do it 5-10mm. Its just the nature of the air spring design + Canada Guy is spot on with his explanation. Don't be too surprised after the shop "fixes" it that it might return later.

    My 2cents if it holds air & works ok just deal with it & be happy. It's a simple design thats reliable
    SPD pedals are an absolute menace to the well-being of the world, and ought be banned immediately.

  9. #9
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    If the fork is stuck down a few mm's then there is really no need for concern. As Canadian Guy mentioned, that's the negative air chamber doing its job. However, if we are talking > 25mm then you have issues.

    Excessive stuck down issues can be caused by air sneaking past the piston o-ring and finding its way into the negative chamber.

    In your particular fork you should have one o-ring on the air piston and two on the negative piston side. I would clean and inspect these for damage - replace if needed

  10. #10
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    the problem with current technology is that everything is becoming (well actually became already) too technical, too precise, too advanced.....to be used without proper maintenance.
    nowadays forks, requires so much service time to keep them up perfect.
    sometimes the factory itself assemble the fork without caring too much on precision and that is why we receive brand new forks with problems.
    All we have to do is to go to a suspension center and pray that they know what they are doing, and magically our brand new fork will be transformed better than new: that is what happen with motocross forks, brand new is good, brand new + service is better than new!
    riders usually buy new forks and service them.

    this is the trick: service before it is warn,sometimes before it is used completely!

  11. #11
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    Took it to the shop. Turned out to be a faulty air cartridge. The replacement was warranty, but paid them to do a rebuild at the same time.

  12. #12
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    Quote Originally Posted by Canada Guy View Post
    I had the same problem with my 2009 Boxxer WC when I first got it. It turned out that when the fork was assembled it was partially depressed leading to create negative pressure on the compression side when the fork tried to return to full travel.
    Thanks for this info! I had a similar problem with a Rev dual air on my woman's bike. She had to run 125psi to get it working. She weighs 80lbs less than me and we had to run the same pressure?
    I took her fork apart, extended it completely and "burped" the lowers. Once back together she's now running 70psi and it's performing much better too.
    Quote Originally Posted by Jayem View Post
    ...People thought they were getting a good fork because it was a "fox".

  13. #13
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    Bordershy and Canada-guy; yep, you are correct. I got the fork fixed by an authorized service center, and they replaced all the seals (or whatever they do for the rebuild). It's been working great, but noticed just last weekend it was about 5-10mm down after a ride. Same thing as before...I could extend it by hand.

    The first time around, it sunk down about half of full travel a couple of times. That's a problem. But 5-10mm doesn't bother me as long as that's all that happens.

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