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Anybody debrained their 08 or 09 Stumpjumper?

2713 Views 24 Replies 13 Participants Last post by  skiology
Hello all,

after having ridden epic 04, stumpjumper 04, stumpjumper 07 I now have an SJ 08 with an AFR Brain. Although this bike is really is the one I like most, especially geometry, I really miss the activeness of the Stumpjumper 04 without a brain.
Even with having it dialed in to the smoothest position, it isn't like without brain.
So now I am thinking of replacing it with an RP23. Other posts on this board - where people replaced their triad - seem promising. However I have as well some doubts because the shock should be designed for the frame which an standard RP23 obviously cannot be.

Another possibility is to change the negative spring rate. I found out on this board that this is possible during an shock service, right?

Or has the 08/09 SJ frame just not the responsiveness that former frame designs had. Comments that specialized does for the 2010 SJ frame say this.

Anybody did something like this? I appreciate any thoughts (expecially speci-suspension tech ;) )

Thanks
mansy
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I have an 08 SJ expert.

My experience. When new, It was ok, but not great, as I came from an 03 Enduro.
The top shock pivot sleeve, was tight creating a lot of sticktion, fixed it and wow much better.
I rode it for about three months and did an air sleeve service, and was stunned, by the lack of any grease about the air piston and can seals. I lubed them and it was like night and day better. Then the platform went out and had to have the whole shock replaced. Got that one back and it has had three air can services all with the negative air left it.

Now my friend purchased an 10 SJ expert and they ride almost exactly the same.
I think the service is crucial to the AFR and it will slowly dissipate the grease (slick honey) and negative air, leaving the performance quite bad.

In short, I would service it and see what you think before dropping $$$ on a RP23
Hello LititzDude,

thanks for the feedback so far. Because my S120 forks lost its brain I will send both fork and shock to service. Your experience is promising.

However I'd like to know wether I can give some information on the way to service so that they can change the internal setup?

Also I appreciate your comments regarding the new stumpjumper. I am really a specialized fan, but with the redesign only 2 years after the 08 SJ I was really disappointed and felt a little fooled.
mansy said:
Hello LititzDude,

thanks for the feedback so far. Because my S120 forks lost its brain I will send both fork and shock to service. Your experience is promising.

However I'd like to know wether I can give some information on the way to service so that they can change the internal setup?

Also I appreciate your comments regarding the new stumpjumper. I am really a specialized fan, but with the redesign only 2 years after the 08 SJ I was really disappointed and felt a little fooled.
Seriously, do yourself a favor, and check the top sleeve bush and make sure it is free to rotate, because if it is tight, it feels like crap, and nothing but a little polishing could fix.

FYI
On the 10 SJ the range of adjustment on the brain fade seems to be more usable. My first shock had all the adjustment in the first 5 clicks, the second is about 6 clicks. I run it at 3 clicks from full firm and it is fairly stout, but good small bump compliance with the air sleeve service and free upper bush.
I have a buddy that de-brained his '07 Stumpy FSR. He hated the brain, couldn't get it set up to his liking. He does ride his bike on the plush side of things. Anyway, he put a RP23 on there and loves it. Says he would never go back to the brain.
I de-brained my '08 SJ Pro and replaced it with a '09 RP23. To me, it made the bike ride much, much rougher. As a basis of comparison, I'm 170 lbs w/ gear, ride the AFR @ 165 psi and the brain 4 click out from full firm and the RP23 was ridden in the #1 (softest)platform setting. I was a little disappointed with the brain performance unitl I rode the same bike with a different shock. Now, I am a firm believer in the brain when it's working. Reliability has been a different issue with me, I'm on my 3rd Specialized shock now. To their defense, Spec has always solved my issues quickly and without question every time I've had one, so I can't knock 'em too bad.
Thanks for explaining your riding experience bikensand because you really have a comparable frame configuration. However I really wonder about your observation, but it really encourages me to do a service.

Thanks again
fsr4000 said:
I have a buddy that de-brained his '07 Stumpy FSR. He hated the brain, couldn't get it set up to his liking. He does ride his bike on the plush side of things. Anyway, he put a RP23 on there and loves it. Says he would never go back to the brain.
That was my thought what would help me aswell. However the 07 frame is more like my 04 stumpy in respect to frame/shock integration. Don't know wether this has something to do with it.
I don't own a bike with a Brain shock, but I have ridden one. From what I could tell Brain is more plush, almost like a Cadillac feel, while RP23 that I have on my 07 SJ is stiffer but you get much better feel for the trail. It was harder for me to tell what the rear of the bike was doing with the Brain shock.
I bought my '08 in the comp model just to avoid the brain. I rode an '07 for several months and could never really get the brain setup to my liking. I then rode an 08 with the brain and still wasn't really pleased.

if i would have kept the 08 it was going to get an rp23 straight from push industries.

And the poster that mentioned the pin being tight in the top of the shock is 100% correct. My new enduro was terrible. To the point of the bolt unscrewing itself and causing the nut to fall off. After getting a new nut and polishing the pin it rides much much better.
funny, It really seems that we have 2 two positions here in the threat.
unfortunately we are talking about an serious amount of money if changing the shock. If not I would really just like to do it for testing reasons.
Just bought a used 08 FSR pro. How often do you guys service the rear shock? I have to look at the bushing. Great thread. Keep it going.
I have an 04 epic with brain and was wondering if I can de-brain it also with RP23. Is this possible? If so, maybe run some kind of handle bar switch to run lockout.
No

mmanuel09 said:
I have an 04 epic with brain and was wondering if I can de-brain it also with RP23. Is this possible? If so, maybe run some kind of handle bar switch to run lockout.
There are no other shock options for your bike and RP23 will not work. The best you could do is get a a shock from an 06 epic that has Brain Fade and IQ. Thats the best shock ever made that will fit your frame.
Pedalfaraway - thanks for the info. I'll keep an eye out for an 06 but really doubt I'll be able to find one. Oh well, I really like my 04 frame however a little heavy by standards these days and would like a little more active suspension. Great bike though.
I had an 04 epic which has an adjustable brain aswell. Here the force when delock takes place can be adjusted. I think they called it brain adjust. After this shock the brain fade came. I got an offer on ebay and tried this shock. Here the force cannot be adjusted anymore, but the oil bypass.
Personally I found the older version with brain adjust better. It gave a more comfortable ride in my point of view. But I think it's a matter of personal taste.
I don't think that you can change the brain shock to anything else. However you may ask to debrain it within a shock service. I heard that this can be done. But you will probably carry the weight of the brain anyway.
So I did it. I serviced the shock and the fork. I paid an incredible amount of money.
I told my dealer that I'd like to have a better responsiveness.

What I got: I got a shock "designes for women". Which should have less compression damping. No real difference in the ride

I am heavily disappointed
I am interested if there are any other shock options as well for my 08 SJ pro. Honestly, with the brain set so that I don't suffer too much bob, the ride is really rough. I've heard other people complain about "no small bump compliance" and now I know what they mean.

On long rides Ibuprofen has become part of my riding program. Lately I've been riding with the brain turned all the way off just so I can have a nice smooth ride, downside is I bob like crazy if I really pedal hard forget standing up.
SJDude said:
I am interested if there are any other shock options as well for my 08 SJ pro.
You can install a 7.5x2.0 RP23 on your '08 SJ. The stock shock is 7.25x1.75. The longer shock/stroke will raise the BB slightly, steepen the headtube angle slightly and add a bit of travel. If you find the geometry doesn't work for you PUSH can reduce the length and stroke to factory specs. There has been a bunch of favorable reports for just throwing 7.5x2.0 RP23 on as it though, I think the geometry change is fairly small.

I have a '09 SJ Comp on layaway right now, and already have purchased a '09 RP23 with medium compression tune, and light rebound to replace the Triad.
Hi justh,

I give specialized a last try and hope for
1) a replacement of the shock
2) that the again new shock will do the trick.

Besides this can you share your experience when using the RP23?
I read the posts of using an RP23 in a stumpjumper, a Talas fork in the front a you will have the same travel like the new 2010 stumpjumper.

However if it doesn't work with the speci shock I am really getting tired about being specialized. There are other brands out there aswell
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