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Discussion Starter · #1 ·
So I took out one of the test Stumpjumpers from my LBS today and took it for a ride at French Creek SP. For those of you that's don't know the PA area, it is one of the premier riding places, lots of rocks roots and some steep climbs. I got about a quarter of the way into my ride and I took the bike off of a 6-8 inch drop with a bit of air. The rear shock must have stuck, because when I to bunnyhop a 4 inch log, the shock bottomed out completely on the landing. I have no idea what happened, because the shock was stuck about three quarters of the way through it's travel. It still reacted to bumps, but it would not return to it's fully extended position even when I tried manually puling the linkage apart. The guys at my LBS are stumped too. Anyone experienced this problem, or even heard of it??? Damn if it didn't ruin a good ride...
 

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Triad, right?

PAmtbiker said:
So I took out one of the test Stumpjumpers from my LBS today and took it for a ride at French Creek SP. For those of you that's don't know the PA area, it is one of the premier riding places, lots of rocks roots and some steep climbs. I got about a quarter of the way into my ride and I took the bike off of a 6-8 inch drop with a bit of air. The rear shock must have stuck, because when I to bunnyhop a 4 inch log, the shock bottomed out completely on the landing. I have no idea what happened, because the shock was stuck about three quarters of the way through it's travel. It still reacted to bumps, but it would not return to it's fully extended position even when I tried manually puling the linkage apart. The guys at my LBS are stumped too. Anyone experienced this problem, or even heard of it??? Damn if it didn't ruin a good ride...
This is not the first time I have read about this from 06 triad shocks. THere have been a couple of members with this type of issue. I am sure that they will chime in at some point.
 

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There is more than a couple posts about this on the "lets talk about shocks" forum. It seems that there is an issue with cold weather affecting the negative pressure chamber in the air shocks. It seems to be affecting all of fox's air shocks. You might want to hit the shock forum for a more in depth answer.
 

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It is called "stuck down" and is a known problem...

with Fox rear shox. Not just the Triad, but the RP3 and the DHX Air are known for doing this as well. What happens is the seal between the negative chamber and main chamber burps air into the negative chamber and basically equalizes or puts more air pressure in the negative. Whether it equalizes or increases the pressure between the two chambers depends on where in the travel stroke this "burp" occurs. This causes the shock to stick down between 1/2 and 3/4 of the way down into the compression stroke. It is NOT a mystery. But it is a big PITA for riders!!! This problem can also be caused by damage to the seal between the two chambers during assembly or re-assembly of the shock either at the factory or during maintenance. In my opinion the problem stems from the seal itself. Fox is using what is called a quad seal. It is a rubber o-ring that has a dual lip on it. They seal quite well but are suseptable to damage during assembly. As far as the cold weather enhancing or causing the problem this is not the first I have heard about it, but am unable to comfirm it one way or the other. But I'd be willing to bet that (since this was a problem in 05 as well) that Fox may have changed the seal material in an attempt to solve this problem and it has created another. But that is just speculation. Anyway, have the shop call Fox, they will tell them how to "un-stick" the shock. It is not an uncommon problem, Fox is aware of it. But thus far to my knowledge has not come up with a permanent fix for it yet. But then I don't work for Fox so I wouldn't know.

Good Dirt
 

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Discussion Starter · #5 ·
Just out of curiosity...

Has anyone heard of this happening to the Brain's on the Epics. Once my brain comes back from CA where Fox is fixing it I want to be able to ride it. Will I have to fear stick down???

Anyway, thanks for your imput, I will foward the info to my LBS so they can fix the problem.
 

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Not that i have seen.

PAmtbiker said:
Has anyone heard of this happening to the Brain's on the Epics. Once my brain comes back from CA where Fox is fixing it I want to be able to ride it. Will I have to fear stick down???

Anyway, thanks for your imput, I will foward the info to my LBS so they can fix the problem.
I do not think it will be an issue with the brain shock, but only time will tell. I am sure it will be fine. For the most part, Fox makes dreat products.
 

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Now that it is cold out I am seeing this happen to just about everyone that is running the shock above 200psi and also is a bigger rider 180lbs+. We have sent the shocks back to Fox only to get them back and have them do it again on the next ride. We now just fix them trail side and ride on.

Fox is turning into a 4 letter word around here
 

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Discussion Starter · #10 · (Edited)
Murchman said:
Now that it is cold out I am seeing this happen to just about everyone that is running the shock above 200psi and also is a bigger rider 180lbs+. We have sent the shocks back to Fox only to get them back and have them do it again on the next ride. We now just fix them trail side and ride on.

Fox is turning into a 4 letter word around here
Unfortunaltely I do not fit into either of those catagories. I weigh 140, and I was running approx 120psi (I think). I don't know why it stuck, guess it was just the fact that it was 27 degrees.
 

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Trail side fix?

Murchman said:
Now that it is cold out I am seeing this happen to just about everyone that is running the shock above 200psi and also is a bigger rider 180lbs+. We have sent the shocks back to Fox only to get them back and have them do it again on the next ride. We now just fix them trail side and ride on.

Fox is turning into a 4 letter word around here
How do you fix this trail side? I had this happen last winter after I got my S-works SJ with a Septune. I rode out and took it to my shop who swapped it out from another frame.

I'm curious incase it happens again (fingers crossed) as it's cold and that seems to be the common thread in all the stuck down issues I've read about. And I fit the profile above: +180 lbs and 210psi in the chamber. :rolleyes:

BTW, the stuck down issue is know well Fox, so much so that they mention it in the manual.

punga!
 

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Do this at your own risk, I don't recommend you do this as it can cause harm to you and or your bike. (now the legal stuff is out of the way)

Let all the air out of the shock, then unscrew the air chamber. Be very carfull when you unscrew it and make sure that nothing is between the air chamber and the end of the shock as the chamber will go flying off to the end and sound like a gun shot. You can really hurt hurself if your hand or fingers or anything else is in the way. Once it's off just slide the chamber back on and screw it tight then re-air and ride on. With the shock still on the bike the chamber will just shoot down the shock and stop at the shock link.
 

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I am not sure that I recommend that.

Murchman said:
Do this at your own risk, I don't recommend you do this as it can cause harm to you and or your bike. (now the legal stuff is out of the way)

Let all the air out of the shock, then unscrew the air chamber. Be very carfull when you unscrew it and make sure that nothing is between the air chamber and the end of the shock as the chamber will go flying off to the end and sound like a gun shot. You can really hurt hurself if your hand or fingers or anything else is in the way. Once it's off just slide the chamber back on and screw it tight then re-air and ride on. With the shock still on the bike the chamber will just shoot down the shock and stop at the shock link.
Not on a new shock, anyways. If anything goes wrong with the shock , it is covered under warranty for 1 year. Unless allowed by fox, taking the shock apart may void the warranty if anything goes wrong. I understand that the seals and air can are designed to be user serviceable, but remember, we are talking about new shocks for the most part. Fox would certainly have an out if the user takes apart the shock trailside, and damages the shock somehow.

That being said, it seems to be a handy tip for someone with the stick down issue, on a shock that is outside the warranty period. Lets not forget that the rider will need a shock pump on the trail for this fix to happen. Not everyone carries one, but I do.
 

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My shop talked to Fox today about the "stuck down" shock. Fox claimed that it was extremely rare. They're sending a new seal kit to replace the previous one. It's an interesting fix since I just had a new seal kit put in my Triad about 2 months ago. I'm not sure if the stuck down is related to the new seal kit, but I'm around 195 lbs with about 220 psi in the shock during a 25 degree ride. I guess the combination was pretty bad. I will say this. My Triad is an '04, and Fox is sending the seal kit at no cost. That's a positive.
 

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Discussion Starter · #16 ·
It's good...

That Fox is sending you a new seal kit. Unfortunately for me, though, I just sent the Brain from my Epic to Fox to have it resealed. It leaked air like a sive; I would lose half the pressure in about 20 min of riding a medium-rough trail, which would leave me with about an inch of sag for the rest of the ride... not good. Originally they just sent my LBS a seal kit, but when the LBS contacted Fox about a possible error in the kit, Fox said that the nitrogen chamber would also have to be recharged to make the shock seal properly or something... so my Brain is now on it's way to Calif... Jeesh. Back to the crappy old HT if I want to ride I guess.
 

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damion said:
Not on a new shock, anyways. If anything goes wrong with the shock , it is covered under warranty for 1 year. Unless allowed by fox, taking the shock apart may void the warranty if anything goes wrong. I understand that the seals and air can are designed to be user serviceable, but remember, we are talking about new shocks for the most part. Fox would certainly have an out if the user takes apart the shock trailside, and damages the shock somehow.

That being said, it seems to be a handy tip for someone with the stick down issue, on a shock that is outside the warranty period. Lets not forget that the rider will need a shock pump on the trail for this fix to happen. Not everyone carries one, but I do.
That's why I had the shop deal with it last winter, but I'm coming up on over an year now. So If I'm 20 miles out and want to get home, it's good to know how. I saw a video on Fox's website a few months ago that shows how to disassemble an older Foat on a work bench to rebuild. His instructions were similar to what they describe.

punga!
 

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Do not forget the pump.

punga said:
That's why I had the shop deal with it last winter, but I'm coming up on over an year now. So If I'm 20 miles out and want to get home, it's good to know how. I saw a video on Fox's website a few months ago that shows how to disassemble an older Foat on a work bench to rebuild. His instructions were similar to what they describe.

punga!
Go ride, and take your shock pump!
 

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The air has gone into the wrong side of the air chamber.

Bigger drops etc which bottom out the shock will push the air in the positive chamber past the piston seal into the negative chamber. I've seen this on floats, rp3s and triad shocks. This can be fixed however. (Be careful, this is dangerous, and this is why fox and its lawyers don't like you doing it.).

Leave the shock in the bike, let the air out and then carefully unscrew the air can. Make sure you wrap a heap of rags around the lower end of the air can, as it will fly off like a rocket, and make sure you keep fingers, genitals etc out of the way. Then use the swing arm to extend the shock. There will be a sort of vacuum in there, and this will be hard to do. Screw up air can and pump up etc. Away you go.

How many times you can do this before the seals etc are stuffed I don't know, and I guess that bad bottoming out would probably damage other parts of the shock as well.
 
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