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Discussion Starter · #1 ·
Went off a 4 ft drop to flat on my 2010 Stumpjumper FSR. Then the shock decided to leak all of its oil, and the blue setting level now doesn't click into position and spits freely.

From a search, it looks like this requires a complete shock rebuilt, and is $150ish. At this price, if I can get an RP23 in place of it, I'm thinking that may be the way to go.

Is there any way to get an RP23 or other fox shock fitting in a 2010 SJ frame, maybe with slight modification? I know there are custom attachments or something on this frame geometry.

Anything Push can do?
 

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Discussion Starter · #3 ·
Push won't tune a Triad.

That's why I'm thinking that if I have to sink in $150 for a rebuild, if I can replace it with an RP23 I'd like to do that instead.

I've read push can change the length of the shock and get it to the 1.9" that the 2010 needs. I'm not sure on the linkage connection, though. I think I'll call push today, they probably know.
 

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Bike Addiction
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I swapped a X-Fusion 7.5 X 1.75 for a Fox 7.5 X 2.00 and had no problems. There is a long thread about the changes in the Speci forum. Search it. It may be some help. I don't think 1.9 to 2.00 would be much to worry about. Def check with PUSH.
 

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noMAD man
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On my '08 Stumpjumper with a 7.25 X 1.75 Triad, I replaced it with a 7.5 X 2.0 Monarch shock, and it worked perfectly. I matched the front by replacing the 120mm fork with a 140mm fork and ended up with a perfect balance. As long as you don't get problematic "chain drag" at the front derailleur or other overextension issues at the rear swingarm, a slightly longer shock will work fine.

I thought the '10 and later Stumpjumpers use some kind of proprietary shock clamp design?...or am I missing an option here?
 

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Bumping this for more info as I am in the same boat.

Has anyone tried contacting PUSH and send in their old TRIAD and RP23 to swap bodies?
 

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Discussion Starter · #8 ·
Push told me I was stuck with my triad due to the way it mounts to the rear linkage. Now, if you send in both an RP23 and the old triad and have them fit the triad stanchion on the RP23, it may be able to be done. But you're looking at about $500 at this point, even if they're willing to cobjob it...

The 2011 Stumpjumper EVO uses a specialized tuned RP23, though, which I bet would fit in the frame and fit the linkage. I think the best way to go would be if you can get your bike shop to part one of these out. It's slightly longer (1/8" IIRC), though, so your BB will sit up higher.
 

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I am getting the opposite length:

2010 Stumpjumper FSR 29 Comp:
"Fox Triad, custom on-the-fly 3-position switch 1) lock out 2) Open 3) ProPedal pedal assisting damping, rebound adj., 7.875x1.8"

2011 Stumpjumper FSR Expert EVO:
"Fox RP23-S with Boost Valve, reb and separate climbing setting and custom 3-position low-speed comp adj., 7.75x2.0"

Could be worth a try just have to make sure that extra 0.2" stroke coupled with the reduced length doesn't interfere with the frame linkage at full compression.
 

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I am getting the opposite length:

2010 Stumpjumper FSR 29 Comp:
"Fox Triad, custom on-the-fly 3-position switch 1) lock out 2) Open 3) ProPedal pedal assisting damping, rebound adj., 7.875x1.8"

2011 Stumpjumper FSR Expert EVO:
"Fox RP23-S with Boost Valve, reb and separate climbing setting and custom 3-position low-speed comp adj., 7.75x2.0"

Could be worth a try just have to make sure that extra 0.2" stroke coupled with the reduced length doesn't interfere with the frame linkage at full compression.
The 2010 26er is 1.9".
Anyone tried fitting the EVO shock on a regular '10 FSR yet?
 

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I think what happens is that the platform/lockout rod sort of get "spit out" from the rebound rod in a hard hit when the nitro pressure in the oil side of the shock does not manage to come though and hold the lockout rod in place. And once pushed out from it's o-ring, you have the leak. At least this is my retrospective schematization after working on this shock. IN fact, I think a problem with this shock is that the oring for the lockout rod/rebound rod intersection is simply a tiny bit to tight, leading to the often reported kind of undefined action of the lockout switch clicker funktion as well as to leaks as described above.

What I did in the end was to simply fill the rebound rod's internals with some epoxy, the re-assebe the shock with the lockout thing (plus I did some shimstack rearranging). Works great, but you have to get into the internals to do it. See http://forums.mtbr.com/showthread.php?t=643165

About replacement shocks. The Triad from my 07 Stumpy is in fact a 7.5*2 shock that is internally limited to 1.8" travel with a nylon washer on the damper shaft (ie the oil side, so you have to dissassamble the shock to mount it unless you think of a smart trick to construct a washer like that that can be mounted without needing to remove the head of the shock from the inner damper shaft).

On my 07, I'm 100% sure that running a regular 7.5*2 would make the link arm hit the main frame before the shock bottoms. Another option (on my 07 120mm travel frame... don't know about newer ones) would be a slightly longer shock with more travel. Those exist (200*56mm, would that be 8*2.2?). Then you would have maybe an inch extra travel but still no frame/link bottom out since the shock is 1cm longer and has 1cm more travel than the original one. But it will still be VERY tight to fit it and depending on some very fine details in the shape of the shock around the lower bushing area it might not work.
 

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Ola H. said:
....
About replacement shocks. The Triad from my 07 Stumpy is in fact a 7.5*2 shock that is internally limited to 1.8" travel with a nylon washer on the damper shaft (ie the oil side, so you have to dissassamble the shock to mount it unless you think of a smart trick to construct a washer like that that can be mounted without needing to remove the head of the shock from the inner damper shaft). ....

On my 07, I'm 100% sure that running a regular 7.5*2 would make the link arm hit the main frame before the shock bottoms. .....
Fox should have these spacers out now. They could also be stacked to further limit bottom travel. And limit air volume appropriately for the shorter stroke.

http://www.pinkbike.com/news/tech-tuesday-How-to-Install-a-Fox-Air-Volume-Spacer-2011.html

I called Fox customer service a few weeks ago about these. CS says they don't limit travel, but I it clearly appears from the pictures that their documentation is incorrect.
 

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I called Fox customer service a few weeks ago about these. CS says they don't limit travel, but I it clearly appears from the pictures that their documentation is incorrect.
To me it looks like these will not limit travel. On one of the pics in the link you can see inside the upper part of the air assembly with the spacer mounted and you can see it does in fact not sit on the damper shaft but is pushed further up into the eyelet assembly. Since this part is thicker, this also explain the shape of the slit in the spacers, I reckon. You can freely slide them over the smaller diameter damper rod and then you push them up to lock onto the slightly larger diameter part where the damper rod screws into the upper eyelet assembly.
 

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To illustrate my point:

Here is the travel reducer spacer, that sits directly on the damper shaft and limits travel (+ reduces air volume):


Here is pinbikes pic which shows the (clear colored) air volume reducer spacer which instead sits inside the upper eyelet assembly and does not reduce travel:
 

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To illustrate my point:

Here is the travel reducer spacer, that sits directly on the damper shaft and limits travel (+ reduces air volume):
I thought the damper outer body, the square end, compressed all the way to the top of the air sleeve, only cushioned by the o-ring (and air spring progression ramp up) from mechanical bottom travel.
 

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Discussion Starter · #17 ·
The 2010 26er is 1.9".
Anyone tried fitting the EVO shock on a regular '10 FSR yet?
The EVO wasn't out when I was looking. If you can get your hands on one, I think it will work since it has the same mount as the normal SJ. The trick is getting the EVO shock when you don't own the bike. If you're in good with a shop, it may work.
 

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No, the square end of the damper body hits the cylindrical part of the air sleve/eyelet assembly that is visible inside the clear air volume reducer (cushioned by the oring). So the air volume reducer never comes into play (exept as an air volume reducer...).
 

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No, the square end of the damper body hits the cylindrical part of the air sleve/eyelet assembly that is visible inside the clear air volume reducer (cushioned by the oring). So the air volume reducer never comes into play (exept as an air volume reducer...).
Thanks for pointing that out. From that picture it does appear there is a depression the Fox air space kit fills. I haven't looked so closely in that area previously, and assumed the travel limit was simply the face of the can.

If ambitious a travel limiting set of slotted spacers, could be stacked and bonded together to prevent sliding off the slot or rattling, to form a similar spacer as the Triad spacer.
 

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That is some interesting information!

On my 2011 Stumpjumper 29er FSR Comp (and I guess that goes for the 2010 aswell), the shock is mounted in that new "unusual" Specialized way.
There seems to be no DU-bushing, just a bolt and the linkage piece.

Is there any difference to a standard fox shock?
Would a standard Rp23 need any modification/machining (aside from the travel spacer?)

My stock Triad is acceptable, but it feels a bit mushy and lacks low-speed compression.
I'd rather swap it for a better shock, than paying big bucks for a service.


Greetings Znarf
 
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