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  1. #1
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    Reba race dual air pressures

    I just got a Fisher with a Reba race dual air. Have noticed the recommended + and- pressures are too high. Are there any suggestions on setting this thing up properly?

  2. #2
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    Quote Originally Posted by mtfrank
    I just got a Fisher with a Reba race dual air. Have noticed the recommended + and- pressures are too high. Are there any suggestions on setting this thing up properly?
    There have been some biblical length discussions on this. Do a search and you'll find plenty of info. But depending on your weight, start with (-) about 20 psi lower than positive. I have it set at 120/100 and I'm 190.
    -jon

  3. #3
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    i like positive and negative to be exactly the same - that gives a plusher feel IMO - ignore the recommendations from rockshox - and start about 10-15 psi lower than they suggest - the right psi is when get approx 20-25% sag

  4. #4
    Schipperkes are cool.
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    If you have Less PSI in the - chamber, the ride will be firmer, less small bump sensitive.

    If you have More PSI in the - chamber, the ride will be plusher, more small bump compliant.
    Quote Originally Posted by mikesee
    Better suited to non-aggressive 125# gals named Russell.

  5. #5
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    See above, or use the chart on the fork, but read the recommended pressure for one weight range lighter than you actually are in.
    The drive towards achievement and success is the motive power of civilization.

  6. #6
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    Quote Originally Posted by mtfrank
    I just got a Fisher with a Reba race dual air. Have noticed the recommended + and- pressures are too high. Are there any suggestions on setting this thing up properly?
    See my BLOG for a basic setup and tuning method.


    R.
    It is inevitable ...

  7. #7
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    whats the best possible psi different from positive and negative to get a plushier feel like the fox? kinda miss my talas and have yet manage to tweak the reba to a satisfactory feel.

    suggestion i am running 120psi + and 100psi -. any idea?

  8. #8
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    The closer you have the difference between the positive and negative chambers, the softer the fork feels on the smaller bumps. However, as you aproach the same pressures in both chambers, you start to lose travel because the negative pressure is making the fork softer and sag more.

    For a softer feeling fork, try going with a difference of 5psi between the two chambers instead of 10psi.

    Just remember that the positive air chamber is like your main spring in a coil fork, and the more negative pressure you use, the weaker you make the main spring.


    R.
    It is inevitable ...

  9. #9
    racerxcaliber
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    neg > pos?

    After reviewing previous threads on Reba tuning I played around with different settings quite a bit. The wrench at my local LBS strongly recommended sticking with the positive setting recommended by Rock Shox, despite what many Reba riders are recommending, in order to get full extension from the fork.

    I am now back to using the Rock Shox rec for the positive, and running the negative chamber 5psi greater. This makes the fork very compliant for small inputs which fits the winter riding available to me.

    Anyone else running negative chamber greater than positive chamber?

  10. #10
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    Quote Originally Posted by Pavlov's Dog
    After reviewing previous threads on Reba tuning I played around with different settings quite a bit. The wrench at my local LBS strongly recommended sticking with the positive setting recommended by Rock Shox, despite what many Reba riders are recommending, in order to get full extension from the fork.

    I am now back to using the Rock Shox rec for the positive, and running the negative chamber 5psi greater. This makes the fork very compliant for small inputs which fits the winter riding available to me.

    Anyone else running negative chamber greater than positive chamber?
    as soon as negative exceeds positive you lose some available travel.....

  11. #11
    Bite Me.
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    Wilks is right to a degree - I run my Reba at 5psi higher negative than positive. You do lose a bit of travel the more negative pressure you run over positive, but it's not a lot (maybe 5mm) and it's not noticable unless you are using all your travel on bigger hits. I compensated for the slightly reduced travel by running about 5 psi lower pressures in both positve and negative than my previous setting (which was 10-15psi less than the RS recommended settings) but still maintaining the higher negative by 5psi. Once you get close to your ideal settings, there's a narrow range of 5 psi either way on the positive an negative that can really dial in the ride for your preferences. I love the fork for this very reason - lots of tuning ability.
    When I see an adult on a bicycle, I do not despair for the future of the human race. ~H.G. Wells

  12. #12
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    Quote Originally Posted by Pavlov's Dog
    After reviewing previous threads on Reba tuning I played around with different settings quite a bit. The wrench at my local LBS strongly recommended sticking with the positive setting recommended by Rock Shox, despite what many Reba riders are recommending, in order to get full extension from the fork.

    I am now back to using the Rock Shox rec for the positive, and running the negative chamber 5psi greater. This makes the fork very compliant for small inputs which fits the winter riding available to me.

    Anyone else running negative chamber greater than positive chamber?

    Running more negative pressure in your fork is robbing you of travel and weakening the main 'spring' of the positive air chamber.

    Also, despite what your local wrench has said, you should be tuning your Reba to suit YOUR riding weight, and not setting it up any other way...irrespective of what Rockshox or your LBS recommends. The Rockshox air settings are waaaay too high.

    Remember, this is a dual AIR fork. The positive air chamber is like the main spring in a coil fork. The more negative air you pump into the negative chamber, the more you weaken your main 'spring'.

    You don't need to run a high positive air pressure to get full travel from the fork. Simply make sure that the positive air chamber pressure is HIGHER than the negative one, and you will get full travel.

    Take a shock pump along on the trail and tune the Reba so that you are getting full travel on the sliders on bigger hits on every normal ride. Then you will find that you don't need high pressures at all for a nice compliant fork.

    Remember the 10 psi rule. If you pump 80 psi into the positive air chamber, you should pump 70 psi into the negative air chamber.

    Tune the fork to suit your weight and riding location / style.


    R.
    It is inevitable ...

  13. #13
    Bite Me.
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    Quote Originally Posted by Rainman
    Running more negative pressure in your fork is robbing you of travel and weakening the main 'spring' of the positive air chamber. R.
    Tastes differ - a "weaker main spring" is another way of saying a more active and compliant fork. You do lose travel, but if you're after compliance, you can trade some travel for that trait. I have the U-turn Reba, so I can add the lost travel by extending the fork a few turns (the bike is spec'ed for a 100mm travel). Taking a shock pump on your rides is great advice - it's a real learning experience to play with the settings.
    When I see an adult on a bicycle, I do not despair for the future of the human race. ~H.G. Wells

  14. #14
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    Quote Originally Posted by Pavlov's Dog
    After reviewing previous threads on Reba tuning I played around with different settings quite a bit. The wrench at my local LBS strongly recommended sticking with the positive setting recommended by Rock Shox, despite what many Reba riders are recommending, in order to get full extension from the fork.

    I am now back to using the Rock Shox rec for the positive, and running the negative chamber 5psi greater. This makes the fork very compliant for small inputs which fits the winter riding available to me.

    Anyone else running negative chamber greater than positive chamber?
    I would start to question anything that mechanic says. Anytime you surpass the positive pressure with the negative you lose travel. Use your rebound and compression for adjusting bump compliance.

  15. #15
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    I'm with Rainman. Also, I'm 215#s and after years of always running undersprung coil forks (waiting for new coils etc etc) It's nice to ride a fork that I can tune to me. I run about 150 in the + and 140ish in the - and love it. But hey, that's just me.
    unityhandbuilt

  16. #16
    Tom Manning
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    Bonking ... not feelin' well I'm so lossed...

    You guys seem to be a lot of veterans. I have a GT I Drive 5. I'm 200 lbs. and I squish my little base model float. What would a good upgrade be so I don't have as much wasted pedaling on CC riding?

  17. #17
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    I agree. I ride a Sugar 292 w/a Reba race, weigh 200 and run 140 over 130. For me the trail dictates my settings: desert and mtn with lots of rocks, and the 10lb difference works better in fast and rocky stream beds than an equal setting. The above pressures work with my riding style, and I generally use 90% available travel on most rides.

  18. #18
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    i wonder u guys running psi base on RS recomendation or base on the sag of the fork. i am a clyde and weight around 280lbs and i only need 120psi on the positive/negative chamber to achieve 20-25% sag on a reba race 100mm. tie a cable tie and sat on the bike in riding position and measure it with a measuring tape. but i see the RS recomendation is 165psi and above or something.

    so i go with the charts or stick to the 20-25% sag rule?

  19. #19
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    Quote Originally Posted by Lordie
    whats the best possible psi different from positive and negative to get a plushier feel like the fox? kinda miss my talas and have yet manage to tweak the reba to a satisfactory feel.

    suggestion i am running 120psi + and 100psi -. any idea?
    If the 120psi positive air pressure is giving you full travel on the bigger hits, then try 120 positive and 110 - 115-psi negative.

    You should be seeing full travel on every normal ride, if not lower your pressures until you are, but keep the positive higher than the negative, and always pump the positive chamber up first.

    Take the fork pump with you and tune on the trails.


    R.
    It is inevitable ...

  20. #20
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    Sorry to perhaps flog a dead horse - but is the recommended psi for the 08/09 models still too high?

    Or should be, is the recommended psi still too high?

  21. #21
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    I'm using 25 psi more in the pos on the 09 Reba, and it's super plush, gets full travel and has no dive in cornering and braking.
    If i use the same settings on my 06, i my as well use a ridged fork. I have to use the 5psi difference rule on the 06 to get a nice plush feel.

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