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  1. #1
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    Back Shock Died

    Wondering if anyone can give me some quick advice...
    I was out doing my usual lappage on T100 today and the next thing I know, my back end is complete mush.
    Rear shock took a dump on me.

    The shock is from a Specialized FSR bought in '04 and it's a Fox Float RLC.
    The three-position lever (pro-pedal) has no effect now at all.

    I know nothing about these... can they be rebuilt easily or once they go south are you forced to just replace?
    Also, since they probably don't make them any more, anyone know a suitable replacement?

    Thx for any help!!
    Hopefully this isn't too far out of line as a topoc here...

  2. #2
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    Talk to your local bike Shop. They can contact fox directly to see if it cab either be fixed, or is under warranty for replacement.

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    You should be able to just rebuild it. The same thing happened to my dads bike a few months ago and he just took it to the local bike shop. Fox has directions on how to rebuild it right on their site so it must not be something thats too uncomon

  4. #4
    sixsixtysix
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    If its an 04 and has never been serviced you're going to want to have someone do a full rebuild on it. It's obviously out of warranty, but Fox will do it, but I am not sure what their cost is.

    The other option is to send it to PUSH Industries in Colorado. They do factory and race tuned rebuilds on most Fox shocks and can probably make it feel better than when it was new. It is a little more on the pricey side @ $150, but it's still cheaper than buying a new $300 shock.

    Here is the link with a list of what they do to the shock.

    http://www.pushindustries.com/servic...20Air%20Shocks

  5. #5
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    Thanks for the help!

  6. #6
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    Quote Originally Posted by grody
    You should be able to just rebuild it. The same thing happened to my dads bike a few months ago and he just took it to the local bike shop. Fox has directions on how to rebuild it right on their site so it must not be something thats too uncomon
    That's only partially true. A user can rebuild the air chamber, as it's made to be user serviceable with a Fox seal kit.

    The damper, which is housed inside the lower portion of the shock, isn't typically user rebuildable, owing mostly to the gas charge that requires special equipment to charge.

    Talk to your local bike Shop. They can contact fox directly to see if it cab either be fixed, or is under warranty for replacement.
    It's from 04. It is now 09, which means it was likely manufactured in 03. Why would it be under warranty going on five years later?

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    http://www.pushindustries.com/produc...tle=Components

    Same thing happened to me. I forget the actual number, but the fox shock should be overhauled after some incredibly small number of hours. You can buy the seal kit from Push Industries....and they have a video on their page that shows you how to do it.

  8. #8
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    All you need is an air sleve seal change. What area of the valley do you live in? Most local shops carry the Fox air sleve seal kit they run about $20 for the kit. To have a shop install the kit for you will run you about $20 so $40 in total depending on the shop.

  9. #9
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    I'm in the north-central Valley.
    Any recommended shops up that way that might be able to whack this out?
    Thanks again!

  10. #10
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    Quote Originally Posted by Steelmonkey
    I'm in the north-central Valley.
    Any recommended shops up that way that might be able to whack this out?
    Thanks again!

    I just talked to Justin at Landis on 7th ave and Indian School (Northwest Corner 602-264-5681) and he has the seal kits in stock ($20 for the kit and $20 labor to install), tell him that Brian told you to ask for him, I used to work at the Southern and 101 location. If you take your bike in today he might be able to get it done for you by tomorow afternoon.

  11. #11
    sixsixtysix
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    Again, a seal kit isn't going to do anything for your propedal. All the seal kit is for is is the main air chamber is leaking. The actual damper unit is what needs to be service, which requires an oil bath, which to my knowledge no LBS is going to do for you.

  12. #12
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    Quote Originally Posted by Steelmonkey
    I'm in the north-central Valley.
    Any recommended shops up that way that might be able to whack this out?
    Thanks again!

    I guess someone should ask this question..... Does the shock hold air?

  13. #13
    sixsixtysix
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    Quote Originally Posted by AzSpeedfreek
    I guess someone should ask this question..... Does the shock hold air?
    Does it matter if it does or doesn't? Going to shop to have the seals replaced might fix a leaking seal, but it's not going to fix any damper issues, which he has stated in the OP that the propedal doesn't work.

    So what then? He drop's $40 on a seal kit and labor only to get the shock back half working and the seals will need to be replaced again the next time it gets opened up to fix the damper.

  14. #14
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    Quote Originally Posted by sixsixtysix
    Does it matter if it does or doesn't? Going to shop to have the seals replaced might fix a leaking seal, but it's not going to fix any damper issues, which he has stated in the OP that the propedal doesn't work.

    So what then? He drop's $40 on a seal kit and labor only to get the shock back half working and the seals will need to be replaced again the next time it gets opened up to fix the damper.

    It matters a lot! If the shock is not holding air then there is no way to know if there is a problem with the damper. When the shock is opened and a seal inside has blown then there will probably be oil filling the inside of the air sleve in whick case the shop will know to send the shock in for a re-build. Also in the process of puting the shock back together, it isn't that hard to know if the damper is blown if you have re-built a few rear shocks.

  15. #15
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    Quote Originally Posted by AzSpeedfreek
    It matters a lot! If the shock is not holding air then there is no way to know if there is a problem with the damper. When the shock is opened and a seal inside has blown then there will probably be oil filling the inside of the air sleve in whick case the shop will know to send the shock in for a re-build. Also in the process of puting the shock back together, it isn't that hard to know if the damper is blown if you have re-built a few rear shocks.

    That may be true with some shocks, but the propeadal can be tricky. once it wears out the only way to fix it is a complete damper rebuild.

    .
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  16. #16
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    One can reopen the air chamber for periodic cleaning and relubing in between seal changes. In general, air chamber seals and glide rings don't really need to be replaced until they become questionable. They don't need to be replaced when the air canister is opened, unless they are damaged, which is unlikely when basic care is taken.

    As far as a blown damper goes, it may or may not be diagnosable with the shock's air chamber off. For example, held upright, if there's a dead spot in the stroke with no air in the chamber, one can reasonably believe there's a damper issue, in low oil levels due to a leak. Next, if the PP isn't working, rebound, controls, or otherwise (one of these conditions applies to the OP), then it's a damper rebuild right off the bat.

  17. #17
    sixsixtysix
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    Quote Originally Posted by Jerk_Chicken
    One can reopen the air chamber for periodic cleaning and relubing in between seal changes. In general, air chamber seals and glide rings don't really need to be replaced until they become questionable. They don't need to be replaced when the air canister is opened, unless they are damaged, which is unlikely when basic care is taken.

    As far as a blown damper goes, it may or may not be diagnosable with the shock's air chamber off. For example, held upright, if there's a dead spot in the stroke with no air in the chamber, one can reasonably believe there's a damper issue, in low oil levels due to a leak. Next, if the PP isn't working, rebound, controls, or otherwise (one of these conditions applies to the OP), then it's a damper rebuild right off the bat.

    Thanks Jerk_Chicken, that was the point I was trying to get across. I have seen more than one Fox air shock where people have blown the damper and thought it could be fixed by the simple seal kit. They end up replacing the seals, riding it with little or no oil in the damper or nitrogen in the negative spring and end up getting the "Stuck Down" syndrome with the shock, which when taking it back apart usually will blow the seals to hell and has the potential of removing a finger if not done properly

  18. #18
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    Sixsixtysix,

    The stuckdown is unrelated to the nitrogen charge in the damper. The negative actually doesn't exist when the air can is off the shock (neither does the main chamber, for that matter). The best way to illustrate for those that have a Float in front of them is to look at the air can and towards the portion where the wiper seals are, one will see a vertical outward dimple, about 6mm long or so. This is actually the air bypass that allows the negative chamber to set and equalize when the piston (attached to the top of the damper shaft) passes over it and then pressure imbalances force them to equalize. This is one reason why when you set your sag, you should really bounce up and down enough to get proper sag and set that negative chamber pressure.

    Inside the damper body (it can also be called a damper shaft), the damper is contained inside, and from it's appearance, one can see right off the bat the disadvantage it can have to a coil damper because it's miniscule in comparison. Small oil supply, but it does work admirably. So the damper stuff is self contained in there, with the N2 charge chamber contained in it as well, towards the bottom where that plugged off valve is. Even if the N2 charge dissipates, it doesn't have anything to do with stuckdown, which was a condition where too much air bypasses into the negative, then doesn't re-equalize back into the main. I had a couple theories on how to eliminate it, which worked in my practice. Perhaps the Fox seals were a bit soft, or undersized, but combined with too-thick lube, such as the grease many used or the heavy Float Fluid/gear oil, especially when cold, the fluid was sluggish and during high speed events, the fluid would be a bit congealed or just too thick otherwise, and create a hydrodynamic wedge, slightly compressing the seal, and then allowing bypass into the negative when the piston passed the negative bypass valve in the canister.

    I had cleaned out the lube and replaced it with lighter shock fluid and previously stuckdown shocks were no longer exhibiting stuckdown without a seal change.

  19. #19
    sixsixtysix
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    Quote Originally Posted by Jerk_Chicken
    Sixsixtysix,

    The stuckdown is unrelated to the nitrogen charge in the damper. The negative actually doesn't exist when the air can is off the shock (neither does the main chamber, for that matter). The best way to illustrate for those that have a Float in front of them is to look at the air can and towards the portion where the wiper seals are, one will see a vertical outward dimple, about 6mm long or so. This is actually the air bypass that allows the negative chamber to set and equalize when the piston (attached to the top of the damper shaft) passes over it and then pressure imbalances force them to equalize. This is one reason why when you set your sag, you should really bounce up and down enough to get proper sag and set that negative chamber pressure.

    Inside the damper body (it can also be called a damper shaft), the damper is contained inside, and from it's appearance, one can see right off the bat the disadvantage it can have to a coil damper because it's miniscule in comparison. Small oil supply, but it does work admirably. So the damper stuff is self contained in there, with the N2 charge chamber contained in it as well, towards the bottom where that plugged off valve is. Even if the N2 charge dissipates, it doesn't have anything to do with stuckdown, which was a condition where too much air bypasses into the negative, then doesn't re-equalize back into the main. I had a couple theories on how to eliminate it, which worked in my practice. Perhaps the Fox seals were a bit soft, or undersized, but combined with too-thick lube, such as the grease many used or the heavy Float Fluid/gear oil, especially when cold, the fluid was sluggish and during high speed events, the fluid would be a bit congealed or just too thick otherwise, and create a hydrodynamic wedge, slightly compressing the seal, and then allowing bypass into the negative when the piston passed the negative bypass valve in the canister.

    I had cleaned out the lube and replaced it with lighter shock fluid and previously stuckdown shocks were no longer exhibiting stuckdown without a seal change.
    Gotcha, that is one of the most on point, concise explanations I have heard as to the cause of the stuck down issue I have seen. I was never really able to get a clear answer as to why it happens, but have worked on a couple shocks that were stuck and taking those thing's apart is a risky proposition without prior knowledge as to what the result's will be. AKA the shotgun blast of the air chamber flying off once its unthreaded. Glad I read up to use a rag through the eyelet to stop it before opening it up.

    Thanks again for the explanation, I know there are a few shock guru's on this site thankfully

    So back to the original problem at hand. If the rebound and propedal are not functioning, it is a damper issue which requires service from an authorized service center.

  20. #20
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    So back to the original problem at hand. If the rebound and propedal are not functioning, it is a damper issue which requires service from an authorized service center.
    Right you are. An air chamber service won't do anything about the damper not working right.

    One of these days I'll post some pics up to better illustrate how the Float works. You've seen the inside and it's pretty cool how they combined parts, such as making the damper the shock shaft with a thru-shaft going to the top cap, and then the damper's cap also being the piston.

  21. #21
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    Thanks for all the info guys! I have done a lot of work on bikes over the years, but I'm seriously deficient when it comes to shocks and (probably easier to mess with) hydraulic brakes.

    Just for future reference (I can look it up if it's a hassle), what's recommended time for doing periodic (major?) servicing of these things? Bike is nearly five years old and I've never had it done (but then I blinked and five years just seemed to fly by). Generally, I only ride between around Sept/Oct and April or so with the occasional run up to Flagstaff. But I'm usually out there two or three times a week.

  22. #22
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    If you're in N. Central PHX, you might be near DNA W. of Scottsdale Rd, S. of 101. Especially if you have one of Specialized Triad's, they've got some good mechanics that can diagnose/rebuild it if you want to keep it local.

    7077 E. Mayo Blvd. suite 100
    Scottsdale, AZ 85054
    480-515-BIKE

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