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  1. #1
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    Reba Race won't hold travel even at higher PSI

    So for a new race bike build I decided to bring my 2005 Reba Race out of retirement. The fork worked fine when I put it out to pasture 18 months ago. Well, I decided to pull it apart and do some preventive maintenance, and apparently I screwed something up.

    Finished the build today and when I went for the test ride, noticed that the fork was reducing to about 30mm of its 85mm travel while just riding along. Rebound is set fairly fast, so that's not the issue. I upped the pressure to see if that would do the trick, no luck there. Fork behaves the same at 70psi as it does at 100psi. One possible clue: when reducing the negative chamber from 100 psi to 70, the fork actually "popped" out to the full 85mm of travel. Once on the bike however, it again reduced to minimal travel.

    My initial guess is that I put too little oil in the damper, does this sound accurate? Sram manual calls for 110ml.

    Your input would be greatly appreciated!
    I'm always looking for new people to ride with. If you are on the Front Range, shoot me a PM and let's go ridin'.

  2. #2
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    Quote Originally Posted by gbug View Post
    So for a new race bike build I decided to bring my 2005 Reba Race out of retirement. The fork worked fine when I put it out to pasture 18 months ago. Well, I decided to pull it apart and do some preventive maintenance, and apparently I screwed something up.

    Finished the build today and when I went for the test ride, noticed that the fork was reducing to about 30mm of its 85mm travel while just riding along. Rebound is set fairly fast, so that's not the issue. I upped the pressure to see if that would do the trick, no luck there. Fork behaves the same at 70psi as it does at 100psi. One possible clue: when reducing the negative chamber from 100 psi to 70, the fork actually "popped" out to the full 85mm of travel. Once on the bike however, it again reduced to minimal travel.

    My initial guess is that I put too little oil in the damper, does this sound accurate? Sram manual calls for 110ml.

    Your input would be greatly appreciated!
    The positive air chamber is leaking air into the negative (air migration, quite common). Need to replace the air piston o-rings.

  3. #3
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    Quote Originally Posted by keen View Post
    The positive air chamber is leaking air into the negative (air migration, quite common). Need to replace the air piston o-rings.
    Thanks for the reply.

    I inspected the o-rings when I serviced the fork, but they all looked fine so I didn't replace any. Guess I was wrong. Is it likely the o-rings dried out when the fork sat unused for awhile? Like I said, the fork worked perfectly fine before I stored it. Do I need to replace the rings on both the positive and negative air pistons?
    I'm always looking for new people to ride with. If you are on the Front Range, shoot me a PM and let's go ridin'.

  4. #4
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    Anybody else have any input before I pull my fork apart this weekend?
    I'm always looking for new people to ride with. If you are on the Front Range, shoot me a PM and let's go ridin'.

  5. #5
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    If you've got them, I'd replace the rings.

  6. #6
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    Quote Originally Posted by gbug View Post
    Anybody else have any input before I pull my fork apart this weekend?
    Replace all the o-rings. Inspect the stanchion walls for irregularities - older air pistons were held on by a roll pin that could back out and score the stanchion wall. I usually add z heavy oil (3-5cc) above the air piston after assembly.

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