DPX2 and special valving for Jam2

[sdcoffeeroaster]

My 2018 Jam2 plus C came with Fox suspension components. While it's been noted here that the Fox 34 Rhythm is not as stiff as we would like, given the 45 lb weight of my bike and my 145-150 lb weight fully kitted, it "might" be OK for me and my riding style. There are not really any used Fox 36 forks that I've found and most have the steerer tubes cut way too short for the Jam2. With a price of around $800-1000. for a new Fox 36, I'm focused right now on possibly upgrading my shock and have been looking at the 210mm x 55mm DPX2. They are available in the states for around $450-$550. My question is if they would be suitable for the Jam2 F.O.L.D. suspension design or would I need a special shock specifically tailored to the Jam's suspension progressive curves. Seems like the latter might be true but I'm not sure if anything like that would even be available in the US since Focus chose to pull out of this market long ago. Does anyone here have experience with a shock upgrade that could comment on this and why advantages there might be with the DPX2 over the standard DPS EVOL that came with my Jam2? I have added a slightly larger volume spacer already but that doesn't give me extra support at the beginning of the load curve where I think the shock is a bit soft. Thanks and stay safe.

 

[Phill_B_34]

Hi, I've upgraded my rear shock to a DPX2.
My local suspension shop only had a 210x50 to suit a Specialized Stumpjumper in stock but had the internals to re-build/tune it to suit my Jam2 210x55 specs. No problem at all.
Talk to your local bike suspension shop (preferable Fox agent/dealer) and see what services the offer in re-building a shock (50 or 55 size) to suit the Jam2.

 

[steve_sordy]

@sdcoffeeroaster Before spending lots of money on a new shock, have you considered trying a ShockWiz?
Review - Quarq ShockWiz | Mountain Bike Action Magazine

I don't suggest for one second that you buy one, but see if you can borrow one or rent one for a few days.

I also have a Focus Jam2 and I too felt that the shock lacked support early on in the stroke. Also that it used too much travel, despite never actually bottoming out. I felt that it was inhibiting climbing by settling into its travel too much. I was about to add at least one more volume spacer. But then a friend of mine offered to lend me his Shock"Wiz!!! Fantastic! Another toy to play with!

After several days of test rides and adjustments, to my considerable self satisfaction, it appeared that I had been almost bang on with my fork and close with the shock settings.

My biggest surprise was that the shock was fine, it needed no spacers, no special tuning, not anything really. My other surprise was that the shock needed more rebound damping than I had set it at. Ever since I was once bounced off a bike because I had packed down I have been wary of too much rebound damping on the shock. The final setting recommended by the ShockWiz was 2 clicks out of 8 away from slow, I had been at 4 clicks away (my start point for first ride had been 6 clicks away).
After completion of the testing and suggested adjustments, the ShockWiz reported that Pogoing, Packing, Bottoming, Bobbing, and Bouncing were all OK. It also surprised me by suggesting that I should make the high speed compression less firm. The HSC adjustment is not one I have on my shock, but the key thing is that it was for HSC to be less firm, not more!

The verdict on the shock that there was no packing down and that I needed no volume spacers was a surprise to me. But I left it as set and resolved to live with it for a few weeks. That was in Dec'19 and it is still untouched. My doubts have gone (and aren't doubts corrosive?) I just ride and enjoy the bike.

If you manage to get hold of a ShockWiz, I will only give you one tip: It is perfectly possible to do the set ups on your own, but save yourself a huge amount of hassle and get a mate to help you and do not skimp on the set up procedure. Trust me on that one.

 

[sdcoffeeroaster]

Wow, another gadget I just have to own. "Luckily" it costs $400., lol....but very cool. I don't know anyone that has one of these around here. I could probably make a small fortune, when the trails open up again, renting it out! Funny you should mention tuning of your shock and fork. After searching for tuning videos I found what I think is a pretty good one online. It showed a technique for tuning the rebound damping that was a bit different than I was trying. You sit on the saddle when you go off of curb and determine if the lack of damping pitches you off of the seat. I was usually standing and trying to look at what the shock was doing instead. I also realized that maybe I was not running enough pressure. I never looked at slack and only at the ring after a hard ride to see how close I was to bottoming. As a result of that I was running about 130 psig and 150 psig seems to get me to 30% slack instead of 40%. I did install the next size up volume spacer (it already had a small one) but only a hard ride at 150 psig will tell me if I needed to do that....probably not.

But I do agree that setting up a suspension is a bit of hit and miss without a tool like that ShockWiz. If it was $100. I would have ordered it already, lol. My bike came with a single volume spacer in the 140 mm 34 fox fork. I did upgrade that to 150 mm and no spacer for a time. I've since gone back to 140 mm and put the volume spacer back in. Running a 29" wheel and going to 150 mm did result in more slack and probably a lot more stress on those wimpy 34 mm forks in spite of my 145 lb weight. I'm back at 140 mm and playing around with the fork damping too. No trails open to really test any of this out right. I guess staying at home has me thinking of all sorts of upgrades for the bike. I'm going to try a 2.6" 3C Minion DHR II on the back for instance. I can see that the 2.8" Minion DHR II sometimes rubs on the sides. This is only my 2nd bike in 3 years of riding. The first one, Giant Anthem 2, also had the Rhythm 34 fork so I really don't know what a high end fork might feel like but they sure are expensive!

 

[sdcoffeeroaster]

Hi, I've upgraded my rear shock to a DPX2.
My local suspension shop only had a 210x50 to suit a Specialized Stumpjumper in stock but had the internals to re-build/tune it to suit my Jam2 210x55 specs. No problem at all.
Talk to your local bike suspension shop (preferable Fox agent/dealer) and see what services the offer in re-building a shock (50 or 55 size) to suit the Jam2.

Thanks. I have found a few 210x55 shocks online. But I'm assuming that the damping unit might have a custom internal calibration for the unique nature of the Focus F.O.L.D suspension and that external tuning might not work out well with a "stock" DPX2. I will contact Fox to see what they have to say about this.

 

[sdcoffeeroaster]

Wow, a fellow rider just told me he has one of these ShockWiz devices and is willing to loan it to me. I'll probably borrow it once the trails open up.

 

[steve_sordy]

.............
But I do agree that setting up a suspension is a bit of hit and miss without a tool like that ShockWiz. .................

I was pleased at how close I'd got by my own efforts.
You may find this guide to suspension setting very helpful. It's from Bike Rumour.
https://bikerumor.com/2014/10/30/bikerumor-suspension-setup-series-full-series-pdf-free-download/

Based upon what I've done with the ShockWiz, I definitely would not buy one, but I would use one again if I thought I needed it. What the ShockWiz did do for me was to provide a disinterested viewpoint.

PS: If I were you, I would find a way to compensate your fellow rider who is lending you his ShockWiz. It is a very generous offer.

 

[sdcoffeeroaster]

I was pleased at how close I'd got by my own efforts.
You may find this guide to suspension setting very helpful. It's from Bike Rumour.
https://bikerumor.com/2014/10/30/bikerumor-suspension-setup-series-full-series-pdf-free-download/

Based upon what I've done with the ShockWiz, I definitely would not buy one, but I would use one again if I thought I needed it. What the ShockWiz did do for me was to provide a disinterested viewpoint.

PS: If I were you, I would find a way to compensate your fellow rider who is lending you his ShockWiz. It is a very generous offer.

I showed that link to another rider and he went out and bought one too, lol. He found one for $235. on ebay, great deal. Yes I'll probably give one of them some coffee since I roast my own for the loan of the ShockWiz or maybe a rental fee.

 

[sdcoffeeroaster]

I was pleased at how close I'd got by my own efforts.
You may find this guide to suspension setting very helpful. It's from Bike Rumour.
https://bikerumor.com/2014/10/30/bikerumor-suspension-setup-series-full-series-pdf-free-download/

Based upon what I've done with the ShockWiz, I definitely would not buy one, but I would use one again if I thought I needed it. What the ShockWiz did do for me was to provide a disinterested viewpoint.

PS: If I were you, I would find a way to compensate your fellow rider who is lending you his ShockWiz. It is a very generous offer.

That is a really great article. I've experienced the chatter they talk about with too much compression damping. In fact it might have contributed to my major crash about 18 months ago where I broke my collar bone, two ribs and scapula in multiple places (follow by 3-4 months of frozen shoulder). I distinctly remember lots of front end chatter right before I went down. Might have been avoided with a better set up....maybe.

 

[Phill_B_34]

I showed that link to another rider and he went out and bought one too, lol. He found one for $235. on ebay, great deal. Yes I'll probably give one of them some coffee since I roast my own for the loan of the ShockWiz or maybe a rental fee.

The way you're going with this, if you can get your hands on TWO Wiz's you can tune front and rear at the same time....

 

[steve_sordy]

Fastening the ShockWiz to my suspension was easy. Syncing to my phone was easy also. But on my own, I didn't find the actual set up very easy at all! You will need to establish the compression ratios for the fork and shock. This will require a lot of physical effort from you. You will be heaving away on the bike and looking at the phone readings at the same time. When you have just fully compressed the suspension half a dozen times and it says "insufficient data" or some other indication of failure, and that you have to do it again, and again! Then you will wish that you had a friend helping you who is bigger and stronger than you.

Top tip: When the device tells you the compression ratio for the fork (and shock), write it down!! The next time you use the ShockWiz on those suspension components, you can just type in the compression ratios and save yourself a huge amount of exertion! To give you an idea of the size of number, my fork was 2.6 and the shock was 2.2. If you get that wrong, the whole ShockWiz program will be futile.

 

[sdcoffeeroaster]

The way you're going with this, if you can get your hands on TWO Wiz's you can tune front and rear at the same time....

Yes a friend did that and then returned one of them after tuning....something I would NOT do, lol. He still has one that he will loan me free and then the friend who bought one recently will rent his out for $20. if I want to try 2 at once. I had a dvo topaz T3 coming. I tried setting my dps up better starting with exactly 30% sag...155 psi. Then I rode it enough with a couple of good hits after I took my volume spacer out (had the 2nd size in, it came with a small spacer...wrong way to go with either for me). I still didn't use the last 14mm of travel. So no spacers, I'm stuck with running even more sag to get it to use all of the travel, making it too soft initially and wallowing too much. I'll try 150 psi next ride while I'm waiting for my new shock to arrive.

That's where I'm hoping I can tune the DVO Topaz to work a bit better. I can't find anyone, my weight 150 lbs, that both has the DVO Topaz and a Jam2. My Jam2 is pretty light at 44.5 lbs also probably not a huge factor. It is coming stock which means medium internal damping. I have some starting pressures to try and will go with no volume spacers at first. But I'm thinking the negative side might need one or two to stiffen up the midrange but will ride it first with the shockwiz and see. That should give me some indication if the internal shims are close for my weight and bike. I hope to get the new shock next week.

 

[ART]

I ride Focus Jam2 Drifter 2019 with DVO Topaz but I am 100kg with riding gear. I Use 255psi

 

[sdcoffeeroaster]

I ride Focus Jam2 Drifter 2019 with DVO Topaz but I am 100kg with riding gear. I Use 255psi

Thanks Art, what did you replace and do you like it?

 

[ART]

Hi,
Replaced Fox Performance. Topaz is a fantastic shock DVO as a brand very good. Now I want to try the DVO Jade X coil but i'm not sure if it fits. Anyone knows if this shock will fit? I saw other guys fitting coil shocks upsite down but it also depens on the external diameter of the coil. Things are too tight in there!

 

[sdcoffeeroaster]

Hi,
Replaced Fox Performance. Topaz is a fantastic shock DVO as a brand very good. Now I want to try the DVO Jade X coil but i'm not sure if it fits. Anyone knows if this shock will fit? I saw other guys fitting coil shocks upsite down but it also depens on the external diameter of the coil. Things are too tight in there!

I think there is a thread on adapting a coil shock to the Jam2 and yes it's pretty close. I was going to suggest the use of a needle bearing but there really doesn't seem to much rotation in full compression of the shock in the Jam2 arrangement to benefit from this. I am going to run my setup thru a ShockWiz device to fine tune things as best I can to my bike and my weight.

 

[ART]

I think there is a thread on adapting a coil shock to the Jam2 and yes it's pretty close. I was going to suggest the use of a needle bearing but there really doesn't seem to much rotation in full compression of the shock in the Jam2 arrangement to benefit from this. I am going to run my setup thru a ShockWiz device to fine tune things as best I can to my bike and my weight.

I have roller beaarings up and down and they are awsome!..what about shockwiz...any good? I'm thinking of buying one

 

[sdcoffeeroaster]

I have roller beaarings up and down and they are awsome!..what about shockwiz...any good? I'm thinking of buying one

I'm not totally convinced the bearings will make much difference with the amount of rotational motion I'm seeing. I let all my air out today and saw very little rotation after marking a starting point. Shockwiz is pretty expensive but my friend here found one for $200. Most say it does a great job but once you're set then you never use it again unless you get another bike. A lot of people rent them out too. Going price new here is about $329. now. I'd rather put that towards a new set of forks someday and just rent or borrow one for now.