Jam2 6.9 Shock Setup

[DubbyMcDubs]

I have been struggling to get a good setup for the rear shock on my 21 Jam2 6.9. I've tried two larger volume spacers (0.4 and 0.6) and various air pressure combinations but its still blowing through the mid stroke quickly and bottoming out on the bigger sections of trail.

The 0.6 spacer has improved the bottoming resistance but feels more harsh. The 0.4 was the best feeling spacer but bottoming resistance was not as good.

Does anyone have any tips? I have seen a number of owners complaining about this issue, is it an inherent design flaw?

 

[Zimmerframe]

Are you running it in Open or Medium ?

 

[DubbyMcDubs]

Are you running it in Open or Medium ?

Open mainly but have tried in Medium as well on occasion. With the 0.4 spacer, it was quite good in the medium setting.

 

[Zimmerframe]

I was struggling with mine and ended up settling for the medium setting as it just seemed to bottom out in open no matter what I did.

It's difficult as you can obviously vary the air pressure and the volume area with spacers but the compression damping settings are arguably a bit limited within the scope of pressures/volumes different riders will be running.

The Factory version has three sub settings within open, not sure how close open/firm is to the normal medium though.

Maybe try something like the 0.6, but with slightly less pressure and run medium ? The lower pressure should take some of the harshness out but hopefully the extra damping will stop you bottoming out ? I guess you could try opening the re-bound a little too, you might just be ratcheting through the travel and it's not getting chance to pull any back - but then that could upset other things.

 

[DubbyMcDubs]

I think I will try the medium setting again with the 0.4 and work my way up from there again. Ultimately I wanted to get it sweet on the open setting but I dont think thats possible.

Interesting that you mention the factory version as I had the same thoughts about whether the additional open sub settings would be what it needs to get it right. But that would be an expensive experiement.

I did dial the rebound back two clicks from Fox standard which was much better to me.

Another thing I may have to try is renting a shockwiz and see what it comes up with.

 

[Zimmerframe]

Yup, I generally like to run my compression as open as possible. Open on this setup seems to be more sort of Barn door open though.

 

[Clue]

I have also had this issue with my Jam2. I like to ride rough terrain and small jumps and could not find the sweet spot between comfort and not bottoming out. I usually ran about 170 psi but one day I went to a bikepark with some friends and figured I needed extra air in the shock. and pumped it up to 250 and didn't bother checking the sag. It worked well in the bikepark and I have kept it the same on trails afterwards and find that I like the compromise.
I run the standard Fox DPS and have installed the yellow volume spacer (0.6 inch3) and weigh about 85 kilo fully kitted.

 

[steve_sordy]

I tried all of the aforementioned stuff on my 9.6 and gave up in the end! and switched to a different shock. I went for the DVO Topaz T3. Absolutely brilliant! and with so much adjustment.

Here is a thread on fitting one to a Jam2:

Anyone fitted a DVO Topaz shock to a Jam2?

I have a size large Focus Jam2 9.6 NINE with a Rockshox Deluxe Debonair 210x55 shock. I am looking at replacing it with the DVO Topaz T3 shock. The problem is the piggyback oil reservoir in that it may hit the TEC pac battery. There are no dimensions of the Topaz to be had anywhere that I can...

www.emtbforums.com

 

[RustyMTB]

This is starting to get to me too. I find the DPS a bouncy castle in open & just on the harsh side in the middle setting, irrespective of rebound setings & I'm running it at 250psi just to get to 25-30% sag. I think it may be time to move it on, nothing against the shock, I'm just not sure it's right for this bike with my fat arse on it.

 

[RustyMTB]

Right, I've been offered a Super Deluxe with a Meg Neg screwed onto it for buttons & I'm very tempted to switch over. Anyone done this & knows it fits? Shock is 210/55 so same dims as the DPS that's on it now.

 

[DenyeR]

The problem you are all facing is the fact that Fold kinematics are too linear in the mid stroke, so you need more compression ramp up to not bottom out, there's lots of ways you can work around this, all depends on the budget.
The absolute best way to achieve this without changing the shock itself is custom valving.
The other thing is that the Fox dps is not a heavy hitting shock, it's designed to work on trail bikes with not so steep and rough terrain, try looking for a shock with nitrogen reservoir to help a bit with the bottom out resistance.
Watch out for shocks with too big negative air chambers like the Fox X2 or RS SDLUXE with megneg as they are generally more linear off the shelf and supple on the top of the travel which is not needed in the FOLD bikes as the layout of the single pivot suspension makes for a supple-comfy initial to mid part of the travel.