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  1. #1
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    Is my luck really this bad? 2011 Stumpy FSR 29er

    So I received my 2011 Stumpy FSR 29er Comp back in late November. According to the front fork specs, I set the + and - chambers to 135 psi. Since day 1 after every ride the + would be about 130 but the - would be around 105-110. LBS tried a bunch of things with no luck, so Specialized sent out a new upgraded RLT Ti fork instead of the original RLT. 5 mins. into my first ride on it the front decompressed and wouldn't rebound. Back up to the LBS that day. Ended up getting ANOTHER new RLT Ti fork from Specialized. So after riding on this, my 3rd fork, after every ride the - is still lower than the + but not as bad as the first one. I'll set them to 135 and after a ride the + is 130 and the - is 115-120. And to top it off, now the rear brake has started the "turkey gobble". I'm really getting disappointed in this bike I don't know much about the technical aspects of the bike, i just like to ride. Any ideas what's with the fork chambers not being equal after a ride?

  2. #2
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    You'll always get some "pump drop" whenever you attach and remove the shock pump. Some of the air from inside the fork pressurises the pump gauge lowering the displayed pressure slightly.

    If you pump the fork to 135psi, detach the pump and immediately attach it again the gauge will show a lower pressure. A drop of 5psi to 130 psi for the positive chamber sounds normal.

    The drop in the negative chamber pressure may be a leak though. There are quite a few threads mentioning internal air leaks on Rock Shox Reba forks. You could try tightening or replacing the schraeder valve core of the negative chamber. You could also consider stripping the fork down and replacing the seals to see if that helps.

    How Often Do You Pump Your Reba?

    Reba lost last inch of travel

    O-Ring Sizes for RS Revelation, Reba, Pike Inside

    Another option to consider if your current fork is mostly working ok would be to send it to a tuning specialist such as PUSH Industries and hope that having them upgrade it gets rid of the niggling problems.

    http://www.pushindustries.com/2009/i...&product_id=37

    .

  3. #3
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    I'd say it's pump drop, as mine does the same thing. The shop where I purchased my bike is very knowledgeable on suspension setups and had me try something out. Do this, put the pump on the shock, air both chambers up to 135, then, disconnect the pump. Don't even compress the fork at this point. Then, reconnect the pump and see if the pressures are down to the approximate 130 setting on the positive, and 110-115 on the negative. If so, it's the pressure dropping from the pump line having to be filled with air. It's worse on the negative side because the negative chamber is much smaller than the positive chamber. I feel your pain, as I went through the same thing with mine and after trying everything I could before taking it back to the shop (they are 60 miles away), they had me do what I described above, and sure enough, that's what it was. For what it's worth, mine is a 2011 Stumpy FSR Comp 29er as well, and my pressure drops 10 psi on the positive side, and 20 psi on the negative side when I do this test. The shop told me that different pumps would yield different pressure drops, as it takes different volumes of air to fill them up. It does sound like the 2nd fork you had was a bad one though, as something had to leak down to keep it from rebounding. I wish I knew what to advise you on the brakes as I've been fortunate on that one and haven't had any problems with brake noise.

  4. #4
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    One big problem with Specialized is that they fell into that hole with every other bike company who specs Avid brakes. Upgrade to Shimano XT brakes and be done with your braking woes, forever.
    ...and proud member of the anti-sock puppet desolation

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    Thats a pretty good idea Mike, and definitely seems likely. So I'll give that a shot when I get in today. As far as the brakes, just buying the bike recently I'm in no position financially to upgrade the brakes now. Wasn't there a warranty bulletin for replacing the rotors from Specialized??

  6. #6
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    As far as fork is concerned, as soon as you get some money send it to PUSH for a full upgrade and tune. I sent my RP23 last year and the difference was night and day. Will be sending my RLT Ti this spring.
    And for brakes, get Formula RX. They are some of the best brakes out there and not very expensive. You might not even have to replace the rotor.

  7. #7
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    Quote Originally Posted by whitesvtcobra
    Thats a pretty good idea Mike, and definitely seems likely. So I'll give that a shot when I get in today. As far as the brakes, just buying the bike recently I'm in no position financially to upgrade the brakes now. Wasn't there a warranty bulletin for replacing the rotors from Specialized??

    I seem to remember something about using the G3 rotor from Avid in a tech bulletin somewhere on here, but my particular bike has them on it already. I assumed that they did this on the 2011 bikes to eliminate the brake noise problems that they had on some of the previous year model bikes. There will be some letters and numbers on the side of the rotor that will tell you which size, and which model they are.

  8. #8
    JTP
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    Quote Originally Posted by ambassadorhawg
    One big problem with Specialized is that they fell into that hole with every other bike company who specs Avid brakes. Upgrade to Shimano XT brakes and be done with your braking woes, forever.
    well said

  9. #9
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    Quote Originally Posted by whitesvtcobra
    So I received my 2011 Stumpy FSR 29er Comp back in late November. According to the front fork specs, I set the + and - chambers to 135 psi. Since day 1 after every ride the + would be about 130 but the - would be around 105-110. LBS tried a bunch of things with no luck, so Specialized sent out a new upgraded RLT Ti fork instead of the original RLT. 5 mins. into my first ride on it the front decompressed and wouldn't rebound. Back up to the LBS that day. Ended up getting ANOTHER new RLT Ti fork from Specialized. So after riding on this, my 3rd fork, after every ride the - is still lower than the + but not as bad as the first one. I'll set them to 135 and after a ride the + is 130 and the - is 115-120. And to top it off, now the rear brake has started the "turkey gobble". I'm really getting disappointed in this bike I don't know much about the technical aspects of the bike, i just like to ride. Any ideas what's with the fork chambers not being equal after a ride?
    I suggest you do get familiar with the tech aspects of your rig. And don't take that in a rude way. What I'm saying is that a little research goes along way towards making you a happier rider. I do agree w/ the pump drop scenario and it can be even worse depending on the quality of your pump and the size/length of the airhose. Some shock pumps "spit off" alot of air when disconnected. Getting your fork dialed in is alot of tune, test, ride repeat, repeat, repeat. Best bet is to carry your shock pump on the trail with you and stop a few times during the ride and check you pressures and make small changes and test them out. I recommend carrying a small notepad as well to record your pressures and notes about how they felt to you. You are on the right track with the + chamber needing to be slightly higher than the - chamber. Invest in a good shock pump with an anti-airloss nozzle. I personally use the Hurricane shock pump purchased a Performance Bicycle. Honestly the largest pump drop I've seen out of it has been 1 or 2 lbs. max.

    As for the brakes: turkey wobble can occur with most all brakes. If avids are set up properly then you shouldn't have many problems.
    Try this:
    remove rear wheel
    take a flat blade screwdriver and insert into the caliper from the bottom.
    "gently" move it back and forth against the pads.
    What you are doing is pushing the pistons back into the caliper.
    Exlixr R's are "self-adjusting" sometimes they are not set up correctly from the factory or can get wacked out on the trail.
    Re-insert the wheel "before" squeezing the leverl (make sure its even and tight in the dropouts)
    squeeze the leverl and this should in laymans terms reset the pads. You may need to site down from the top of the caliper and loosen the bolts and make slight alignment adjustments.
    Otherwise, take the shop for a possible brake bleed. Avid systems are often filled with way too much fluid from the get-go.

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