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Discussion Starter · #1 ·
Based upon all the posts on the Fox air shock "stuck-down" problem it looks like it has not gone away. After studying the Fox patent (6,135,434) it is apparent that the problem occurs when the sliding seal inside the sleeve leaks momentarily while the shock is compressed. The high pressure air from the "air spring" side moves into the negative pressure chamber. This increases the negative pressure causing the shock to stay compressed. When this happens on the trail, the bike is difficult to ride because of pedal to ground interference.

The fact that the shock stays compressed indicates that the seal is no longer leaking (otherwise the pressures would equalize and the nitrogen fill in the damper assembly would force the shock open. I suspect that the momentary leak is caused by twisting of the seal or some other dynamic problem that only occurs during rapid movement of the piston. The "cold weather" theory may also be one of the factors, since low temperatures shrink the seals and make them stiff.

If there was a way to manually vent the negative pressure chamber it would allow the rider to de-compress the shock, pump it up to the correct pressure, and get home.

In looking at my Triad (2006 Stumpy FSR) there doesn't appear to be enough metal thickness in the sleeve to install a vent valve.

Suggestion to Fox........ add a boss on the sleeve with a small manual vent valve. This would also eliminate the potential injuries due to the sleeve flying off during disassembly of a stuck-down unit.
 

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Mud Boy
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Interesting theory

this "stuck down" condition reared it's ugly head with the 06 model year air shocks didn't it? Did it occour prior to 06? It certainly continues in the 07 model year, as I have an 07 RP23 that I installed as a replacement to my 06 Triad(POS), and it stuck down on the second ride.

If this is an on going design flaw, how will Fox step up to the plate? It seems that one seal change solves the problem for most. The fact that Fox initially said that a supplier substituted an inferior seal material without their knowledge, has no credibility anymore. That problem should have been corrected prior to the next model year of production
-2007..

Anyway, you know the line...enquiring minds want to know
 

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This also happened to my fox that was on my 2005 enduro. It was new bike that I got on a closeout sale. I took the shock back to my lbs so they can send it back to FOX. Well this was over a month ago. All I get from my lbs is that Fox is running slow that it should be here any day now. I did get a call last week that I will most likly get a new shock instead on mine being rebuild. I all know that I will never buy a Fox shock just because of the customer support that Foxs has shown me. If the replacment shock does not work out I will not send it back to FOX. I will get it rebuilt at push industies. Or go with a different brand of shock. It is most likly that I will not even shop at the same lbs that sold me the bike. FOX YOU HAVE LOST ME AS CUSTOMER. Good luck with your shock and I would like to know things work out for you. Ben
 

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Ben99r1 said:
I will get it rebuilt at push industies.
If your talking about the DHXA, Push doesnt work on them.

wayne
 

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Ben99r1 said:
This also happened to my fox that was on my 2005 enduro. It was new bike that I got on a closeout sale. I took the shock back to my lbs so they can send it back to FOX. Well this was over a month ago. All I get from my lbs is that Fox is running slow that it should be here any day now. I did get a call last week that I will most likly get a new shock instead on mine being rebuild. I all know that I will never buy a Fox shock just because of the customer support that Foxs has shown me. If the replacment shock does not work out I will not send it back to FOX. I will get it rebuilt at push industies. Or go with a different brand of shock. It is most likly that I will not even shop at the same lbs that sold me the bike. FOX YOU HAVE LOST ME AS CUSTOMER. Good luck with your shock and I would like to know things work out for you. Ben
fox I hope you are reading this and hire some more staff. It sounds like their turnaround times are starting to suck, for what it's worth they used to be a lot quicker a few years ago.
 

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Surestick Malone said:
Yup, had this happen several times on a FloatR from a '99 iDrive
My dad has had it happen twice on a Float off an '04 FSRXC and I have had it happen once on my Float RL off my '04 Enduro.
 

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well...

Most competent shops should be able to fix a stuck down shock in 10 minutes (at least un stick it), I know because I've seen them do it at my LBS. It's just a matter of unscrewing the canister while the shock is a vice and standing clear in case it shoots off. (think the mech. put a screwdriver through the shaft eyelet to prevent it from flying across the room).

I had a 05 Septune (RP3 with 7 levels of squishy pro-pedal) that got stuck down very early on. At that point, no one really knew what to do, so they sent it back to Fox and gave me a new one off another frame the shop had (I have a good relationship with the shop). It happened again to an 06 Brain-equipped S-works that I was borrowing from the shop while they had my fork in for repairs). This time, the mech. removed the shock from the frame, mounted in a vice and released the pressure while I waited. I was in and out of the shop in 20 minutes (took him longer to remove and replace the shock than to actually fix the stuck down). Never had any problems after that with the loaner and my 05 Septune has been working to this day (now that I say that, I'll get stuck down on my night ride tonight):rolleyes:

Either way, this problem has existed at least since 2004 (05s came out in Oct 04). And less you have vice with you, its not very easy to fix trailside. Someone here posted in a thread that there was a way to do it, but didn't recommend it for the masses. It involved unscrewing the canister while still mounted. You can do all kinds of damage this way if you're not careful.

punga!
 

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We want... a shrubbery!
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Problem well before 2006...

As another user commented, I have a stuckdown '99 FloatR sitting in my toolbox right now, it's been sitting there for a while come to think of it...
 

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After getting my 2005 rp3 stuck down twice, I forced myself to do the manufacturer's recommended maintenance, and it has been a problem since. Relubing the airsleeve seal with fox fluid on a regular basis seems to prevent the leak for me. It takes 5 min once its off the bike. It also keeps the thing silky smooth.
 

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I haIve run into a stuck down float many a time and am a believer in the cold wheather theory, as my float does this every winter. All is correct above: a leaking of pos. into neg. holding shock compressed. however the fix is way easier than any of the suggestions i read above aside from keeping seals moist. on tho piston housing (female piece) you will find a small raised notch this notch is where you will slide a tool you create in to unseat the seal keeping the neg air chamber compressed. Once seal is unseated male piece will extend back out and a decompressing of air is heard. If shock is not due for a seal maintenance simply reinflate and ride. can be done on or off bike. The tool you are creating is a simple feeler gauge my first was a spoke heated and pounded until flat enough the second was a smaller gauge steel dowel heated and pounded final product is less than a .25 inch wide and slim enough to slide between male piece and housing at notch and only needs to be 4-5 inches long with only the 1st 3 inches pounded flat. solved my cold weather problems.
 

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Discussion Starter · #12 ·
brymihay said:
I haIve run into a stuck down float many a time and am a believer in the cold wheather theory, as my float does this every winter. All is correct above: a leaking of pos. into neg. holding shock compressed. however the fix is way easier than any of the suggestions i read above aside from keeping seals moist. on tho piston housing (female piece) you will find a small raised notch this notch is where you will slide a tool you create in to unseat the seal keeping the neg air chamber compressed. Once seal is unseated male piece will extend back out and a decompressing of air is heard. If shock is not due for a seal maintenance simply reinflate and ride. can be done on or off bike. The tool you are creating is a simple feeler gauge my first was a spoke heated and pounded until flat enough the second was a smaller gauge steel dowel heated and pounded final product is less than a .25 inch wide and slim enough to slide between male piece and housing at notch and only needs to be 4-5 inches long with only the 1st 3 inches pounded flat. solved my cold weather problems.
Now that's a creative solution!

Have you tried it on a Triad?

My 2006 Triad doesn't have a notch and the gap between the housing and piston (where the wiper is) looks very narrow, probably less than 0.1 inch.
 

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Ben99r1 said:
This also happened to my fox that was on my 2005 enduro. It was new bike that I got on a closeout sale. I took the shock back to my lbs so they can send it back to FOX. Well this was over a month ago. All I get from my lbs is that Fox is running slow that it should be here any day now. I did get a call last week that I will most likly get a new shock instead on mine being rebuild. I all know that I will never buy a Fox shock just because of the customer support that Foxs has shown me. If the replacment shock does not work out I will not send it back to FOX. I will get it rebuilt at push industies. Or go with a different brand of shock. It is most likly that I will not even shop at the same lbs that sold me the bike. FOX YOU HAVE LOST ME AS CUSTOMER. Good luck with your shock and I would like to know things work out for you. Ben
Update on my last post. I heard from my lbs yesterday they told me it mite come in next week. If it does show up that will make it six weeks to get my shock back from my lbs. So good luck to everyone that is going thur this problem.
 

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Ben99r1 said:
Update on my last post. I heard from my lbs yesterday they told me it mite come in next week. If it does show up that will make it six weeks to get my shock back from my lbs. So good luck to everyone that is going thur this problem.
Hmm. The mechanics at my LBS have always been able to fix the problem right there in the shop while I wait.
 

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brymihay said:
I haIve run into a stuck down float many a time and am a believer in the cold wheather theory, as my float does this every winter. All is correct above: a leaking of pos. into neg. holding shock compressed. however the fix is way easier than any of the suggestions i read above aside from keeping seals moist. on tho piston housing (female piece) you will find a small raised notch this notch is where you will slide a tool you create in to unseat the seal keeping the neg air chamber compressed. Once seal is unseated male piece will extend back out and a decompressing of air is heard. If shock is not due for a seal maintenance simply reinflate and ride. can be done on or off bike. The tool you are creating is a simple feeler gauge my first was a spoke heated and pounded until flat enough the second was a smaller gauge steel dowel heated and pounded final product is less than a .25 inch wide and slim enough to slide between male piece and housing at notch and only needs to be 4-5 inches long with only the 1st 3 inches pounded flat. solved my cold weather problems.
wow, can you post some pics of the tool and how to do this? thanks
 

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Ben99r1 said:
This also happened to my fox that was on my 2005 enduro. It was new bike that I got on a closeout sale. I took the shock back to my lbs so they can send it back to FOX. Well this was over a month ago. All I get from my lbs is that Fox is running slow that it should be here any day now. I did get a call last week that I will most likly get a new shock instead on mine being rebuild. I all know that I will never buy a Fox shock just because of the customer support that Foxs has shown me. If the replacment shock does not work out I will not send it back to FOX. I will get it rebuilt at push industies. Or go with a different brand of shock. It is most likly that I will not even shop at the same lbs that sold me the bike. FOX YOU HAVE LOST ME AS CUSTOMER. Good luck with your shock and I would like to know things work out for you. Ben
Both our fox(mine and my wifes) triads both have been stuck down.They were really good at the shop and gave me another for my bike off another stumpy but my wifes was sent away for warranty.THose guys are a nitemare..................they took over a month to get the triad back and over a month to get her fox 40 back.....FOX GET YOUR S H I T TOGETHER......................you have lost us as customers as well!!!!!!!!!!!!!!
 

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punga said:
Most competent shops should be able to fix a stuck down shock in 10 minutes (at least un stick it), I know because I've seen them do it at my LBS. It's just a matter of unscrewing the canister while the shock is a vice and standing clear in case it shoots off. (think the mech. put a screwdriver through the shaft eyelet to prevent it from flying across the room).
The Fox maintenance video suggests using a rag through the eyelet as a screwdriver could damage something. Some concept though.
 
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