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  1. #1
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    Air Settings You Use For Dual Air Forks

    Hey Guys, Just wondering your air pressure you use in your forks. I think that i have mine wayyyyy to high but i just want to know. I run +120 and -125 @ 185 lbs.

  2. #2
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    Something I want to know is do you have to have any air in the negitive chamber if you want full travel on a dual air. Wouldn't the shock just function like any air shock without dual air if the negitive chamber didn't have any air.

    I do run my air WAY to high, Think 100psi, but I was told to run the air the way I liked it and this amount of air lets me use my full travel while not bottoming out on anything but the largest drops.

    Edit, Sorry I run 150psi in the rear, in my fork I run about 100 in the +ve and 70 in the -ve, If i put any more in the -ve it starts to pull the travel down, I weigh like 130lbs. but if I run any less air the shock bottoms out in the riding I do.
    I think I am running my air wrong though any one have a suggestion for me.
    Last edited by FeltDH; 11-04-2010 at 06:20 AM.
    Ridin' fo' dayzz

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  3. #3
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    See, I dont do many drops or jumps, I just want small bump compliance. Any ideas? I know my shop told me to always run air in the negative air chamber, if not it will damage the fork. Not sure why though..........

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    You want to read this entire thread: Reba fine tuning

  5. #5
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    I have a Reba, and a Sid World Cup both with dual air. I
    weight 160 and run 110 pounds of air in both chambers.

    Best, John

  6. #6
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    how will it damage the fork if there is no air in the -ve chamber, doesn't the -ve chamber pull the fork travel down a lot if you run it higher than the +ve air
    Ridin' fo' dayzz

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  7. #7
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    Quote Originally Posted by FeltDH
    how will it damage the fork if there is no air in the -ve chamber, doesn't the -ve chamber pull the fork travel down a lot if you run it higher than the +ve air
    I called my lbs and they said that no negative air pressure in a dual air fork is the dame thing as putting to high of a pressure in one of the canisters, a no no the manual says specifically not to do. Sounds like a perfect recipe for a blown seal to me plus the fork will be extremely unresponsive.

  8. #8
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    I weigh 125lbs and run about 65psi in the positive and 40psi in the negative.
    The negative chamber assists with the compression stroke.

  9. #9
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    Air in the Neg also stops the fork from clunking out when it's extending again.

  10. #10
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    7-10psi more in the neg on my reba world cup makes me hardtail xc bike feel like a plushmonster. Small bump compliance is goddamn buttery amazing.

  11. #11
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    Definitely read the post linked above. In short, keep the negative at or below positive.

  12. #12
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    Quote Originally Posted by redmr2_man
    7-10psi more in the neg on my reba world cup makes me hardtail xc bike feel like a plushmonster. Small bump compliance is goddamn buttery amazing.
    Do you get all of your travel, give or take?

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    you lose 5? mm to purely small bump compliance by doing this, but yes I get full travel.

    Everything I've ever read, indicated 5-10 psi MORE negative than positive. Not sure why you'd do it the other way.

    edit: after reading anden's post and that one moderator, both make pretty good points.



    What I know, is that the fork feels leaps and bounds better with 5-10psi more negative than postive, compared to more positive, or equal psi. It's night at day. Small bump compliance is borderline amazing.

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    Quote Originally Posted by redmr2_man
    you lose 5? mm to purely small bump compliance by doing this, but yes I get full travel.

    Everything I've ever read, indicated 5-10 psi MORE negative than positive. Not sure why you'd do it the other way.

    edit: after reading anden's post and that one moderator, both make pretty good points.



    What I know, is that the fork feels leaps and bounds better with 5-10psi more negative than postive, compared to more positive, or equal psi. It's night at day. Small bump compliance is borderline amazing.
    Yea, I totally agree, but the manual says not to do it.

  15. #15
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    Meh, when I recently had the factory fork system from PUSH installed in my 2009 Revelation, they set the positive and negative PSI the exact same. After 1 ride on it, I haven't felt the need to change it yet, but I haven't had much time on it.

    BTW, if I recall correctly...I believe the manual does say you can put more negative than positive, just not to exceed a certain amount, and to always fill the positive chamber first.
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  16. #16
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    The negative pressure component of RS Dual Air forks has always seemed very poorly named in my opinion, since you're pumping air INTO it. In any case, that thread mentioned above really is the thing to read in terms of tuning RS Dual Air forks with Motion Control damping. It really helped me sort out my Revelation.

    Having said that, I've moved to a Solo Air Lyrik and it's light years better. Don't know if it's the Solo Air system always metering out the correct & equal amount of pressure to +ve and -ve chambers, or the Mission Control damping over Motion Control. But whatever it is, it's the better fork.

  17. #17
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    where to start?

    new rockshox revelation race dual air fork,weigh 250 where do i start with positive and negative pressures?
    thanks

  18. #18
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    Quote Originally Posted by turfbike
    new rockshox revelation race dual air fork,weigh 250 where do i start with positive and negative pressures?
    thanks
    Try around 150psi in both and work from there. The important thing is to get around 30% sag. Don't worry too much about set numbers, just dial in the correct sag. That being said, the 150 should be a good point to start from for you.
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  19. #19
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    Quote Originally Posted by nuclear_powered
    The negative pressure component of RS Dual Air forks has always seemed very poorly named in my opinion, since you're pumping air INTO it. In any case, that thread mentioned above really is the thing to read in terms of tuning RS Dual Air forks with Motion Control damping. It really helped me sort out my Revelation.

    Having said that, I've moved to a Solo Air Lyrik and it's light years better. Don't know if it's the Solo Air system always metering out the correct & equal amount of pressure to +ve and -ve chambers, or the Mission Control damping over Motion Control. But whatever it is, it's the better fork.
    it's likely the mission control and the larger stanchions. my totem solo air felt better than any dual air fork i've had, but it also has 25% larger stanchions. i run my rev @ about 95psi + and - varies depending on what i'm doing. i weight 145lbs +/-

  20. #20
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    Thanks, this all helps as well as the other threads, I will try to screw around with my fork some more, I really haven't had time to lately so I was just running it at what I set it up as originally.
    Should I try running around 90-95 in -ve and 100 in +ve or should I go the same with both
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  21. #21
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    run 5-10 more psi in the negative air chamber than the positive and report back. You'll have way better small bump compliance.

  22. #22
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    Quote Originally Posted by redmr2_man
    run 5-10 more psi in the negative air chamber than the positive and report back. You'll have way better small bump compliance.
    I'll try this and see what happens, only thing the Bike season is over and I'll only be getting over to the mountains a few more times before snow but I can try to get some riding in on my own trails. Thanks for the help
    Ridin' fo' dayzz

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  23. #23
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    Quote Originally Posted by redmr2_man
    you lose 5? mm to purely small bump compliance by doing this, but yes I get full travel.

    Everything I've ever read, indicated 5-10 psi MORE negative than positive. Not sure why you'd do it the other way.

    edit: after reading anden's post and that one moderator, both make pretty good points.



    What I know, is that the fork feels leaps and bounds better with 5-10psi more negative than postive, compared to more positive, or equal psi. It's night at day. Small bump compliance is borderline amazing.
    I always contend that running your fork the way it feels best for you is the way to go. Now having said that, from my own experience having the neg above pos creates awesome SBC, but it was impossible to achieve full travel due to the spring rate ramping up super quick near the end of the stroke. That was negating about 25% of my entire travel by "bottoming out" too soon. I also had to run much more pressure to have equal sag. Lowering the pos pressure for proper sag and then filling the neg to about 10-15psi less gave the best feel all around and I have full travel too. The trade off with awesome SBC is pedal bob and energy loss. When compression damping and floodgate come into play, you lose the SBC you once had, so it was a moot setup for me. But I agree that the SBC was fantastic. It just didn't work for everything I wanted it to do.

    Not sure about 2011, but my 2010 Dual Air allows 15psi more than positive according to the manual. Those worried about damaging their fork by running slightly higher neg shouldn't worry.

  24. #24
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    See, I dont do many drops or jumps, I just want small bump compliance. Any ideas? I know my shop told me to always run air in the negative air chamber, if not it will damage the fork. Not sure why though..........
    I too am new to air forks. I think I've only own them for about 3 mos now but I've been adjusting it every other day until last week. I have SID--XC and Revelation--Trail. I did follow and used some of the guys advice here and here's what I have came out with.

    1. drops/rocky/rooty terrain
    2. small bumps/fire roads/single track trails

    For #1: I have it setup to what the spec sheet says. I weigh in at 145 and the spec says 90-105 psi (+/-chamber) I put mine to 90 psi + and 95psi -. Compression at FULL OPEN. This makes the the front wheel go over those big bumps (almost like running coil forks) and a little bit small bump compliance.

    For #2: I have it setup to less air on both +/- chamber. If the trail has no drops, I'd go with 70psi + and 75psi -. This makes the fork more plush and small bump compliance but not good for going over stair like drops or big bumps obstacles.

    Good luck!

  25. #25
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    Quote Originally Posted by John Kuhl
    I have a Reba, and a Sid World Cup both with dual air. I
    weight 160 and run 110 pounds of air in both chambers.
    Just to show how big of a range different people run, I weigh about the same (actually165), also have a Reba and Sid and run +80 and -70 in the Sid set at 80mm, and +65 and -60 in the Reba set at 100mm. I also have a Recon solo air, and run only between 50-55 set at 130mm.
    I started much higher on these forks, and gradually reduced until I found I was using most of the travel on bigger hits.
    Warning: may contain sarcasm and/or crap made up in an attempt to feel important.

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