Polaris RZR Forum - RZR Forums.net banner

1 - 20 of 69 Posts

·
Registered
Joined
·
1,315 Posts
Discussion Starter #1 (Edited)
Does anyone have a shock valving recipe to share? I have a two-seat XP turbo. It has the fox internal bypass shocks. Stock, there's 24 clicks of compression adjustable total, I had the front shocks 21 clicks in and the rear shocks all the way out at zero. I found the front springs to be way too soft and the rear springs to be too stiff. So with the compression adjusted that way the car seemed to ride fairly well. I just installed the shock therapy 3+ spring kit, which consists of four new front springs and the crossover, and two new upper rear springs with the crossover. I've only had it out for about an hour drive and it's much much improved. I'm trying it with 0-6 clicks in to start with. I also adjusted the crossovers up from the recommendations because it was still too firm.

I've re-valved my own shocks on my super duty, they're bypass shocks. I've also set up the suspension on a race rhino that I built and a pre-runner. So I know how to do shock work. But, these internal bypass shocks are a little more complicated.

I've heard over and over that shock therapy can do wonders with them, but I really don't want to spend $750 for something I can do my self for probably $40 in shims. I have not contacted pound sand to see what his prices are. And there's a couple of guys local to me that supposedly can we do them for $260 or something, but again, that's more than $40. And I would really like to do them myself.

I think what needs to be done is drill the bypass ports out a little bit to give a smoother ride at slow speed and washboards, and make the valving a little stiffer so you have a better bump zone. Also, maybe put a flutter stack in, and maybe just in the rear only?

Below are a couple of pictures of the Manual showing the shock specs, and that translated to the fox valving chart shows the rear at a 90 pound compression, and 80 pound rebound. It puts the front at 90 pound compression and 70 pound rebound. Buy pound, I'm referring to the # number in the fox valving chart.


12/13/17
So I revalved the rear shocks. I’ll post up what I did after a proper test. Here’s a vid I made showing the internals.

1/14/17
I revalved the rear shocks a second time. Rebound is
1.6x.010
1.425x.010
1.35x.010
1.1x.010
.950x.010
.800x.020
.800x.020
.800x.020

I also replaced the 1.8x.015 compression shim with a .012 and cut down two of the bypass check valves.

The car works extremely well now. It’s just a hair light on rebound at slow speeds, but works well at 40+ mph. There is no donkey kick. It handles 1.5 foot whoops at 60-70 mph.

I’m happy with rear shocks now, and the stock fronts so far seem good to me. I have the rear clicker all the way out (full soft), and I started with the fronts at 15 in, then backed out to 12 in, then went down to 10 in. I still haven’t ran it against a full ST car yet, but I’d like to, and video them so I can see how they compare.

You can see what I cut on the bypass check plates below.
 

·
Captain/Paramedic
Joined
·
82 Posts
Well you already went with the Shock Therapy springs. So why not let them do the valving. The guys at shock therapy have spent a ton of time doing valving and real world testing on their products. I have the stage 4 kit on my 2016 XPT and it is nothing short of amazing. It maybe on the pricey side to you but it is well worth it. You need to realize that Shock Therapy has to try and recover some of the cost of their R&D. Their product is well worth the money. IMO you will not find a better suspension for the money,
 

·
Registered
Joined
·
2,115 Posts
Well you already went with the Shock Therapy springs. So why not let them do the valving. The guys at shock therapy have spent a ton of time doing valving and real world testing on their products. I have the stage 4 kit on my 2016 XPT and it is nothing short of amazing. It maybe on the pricey side to you but it is well worth it. You need to realize that Shock Therapy has to try and recover some of the cost of their R&D. Their product is well worth the money. IMO you will not find a better suspension for the money,
A canned tune is not for everyone everywhere. Custom tune to your style and terrain is worth its weight in gold.
 

·
Premium Member
Joined
·
1,954 Posts
Well you already went with the Shock Therapy springs. So why not let them do the valving. The guys at shock therapy have spent a ton of time doing valving and real world testing on their products. I have the stage 4 kit on my 2016 XPT and it is nothing short of amazing. It maybe on the pricey side to you but it is well worth it. You need to realize that Shock Therapy has to try and recover some of the cost of their R&D. Their product is well worth the money. IMO you will not find a better suspension for the money,
A canned tune is not for everyone everywhere. Custom tune to your style and terrain is worth its weight in gold.
Shock therapy is not a canned tune. They have different springs and valving based on where you ride, type of terrain, driving style, weight in the car, weight of accessories, etc.
 

·
Registered
Joined
·
1,315 Posts
Discussion Starter #6
Just looking for any information on doing this myself. And to help others that are able to DIY. As I mentioned, ST does a good job, but at $750 vs DIY for the cost of shims, plus the satisfaction of doing it myself = priceless!
 

·
Registered
Joined
·
1,315 Posts
Discussion Starter #7
I've already had one guy message me and tell me that a combination of my ideas in the first post are what works good for him.
 

·
Registered
Joined
·
45 Posts
Interesting thoughts. I am in the same boat. I hate they way my XPT handles now. Most definitely needs less rebound in the front and more in the rear, probably more spring in the front and less in the rear, and the steering wheel just doesn't seem to be of much use, mine pushes like a dump truck. You gotta throw it off in the corner and stab the throttle and break the tires loose to get it to turn.

I am pretty sold on the Shock Therapy package, but like you, the price is holding me back. The rear sway bar seems a little expensive, and the shock service seems a little expensive. But, they have to pay for the overhead and R&D somehow.

I did shocks for a living for a couple years, never progressed much past following known builds, but I did learn that without putting them on a dyno, you're kinda shooting in the dark. Even with pieces that are supposed to be the "same" as one another, they almost never dyno the same. When you start talking about drilling bypasses, changing bleed, etc., I am not sure that can legitimately be accomplished without a dyno.

I can't seem to talk my way into either route!
 

·
Registered
Joined
·
1,315 Posts
Discussion Starter #9
There is a thread on the Maverick formum called x3 RS suspension tuning by Gary, he's out of lake Havasu with a company called UTV shocks, and according to one poster he is one of the top six shock tuners in the world. It sounds like he took the shocks apart, they're the same exact shocks that we have, he probably took them apart 20 or 30 times I'm guessing. In the process, he wound up welding up the bypass ports and moving them and making new ones. He's got the car working really really good now. But, since he's such a good tuner and it took him that many tries to get them right, that's why I'm afraid to even start on this by myself without some kind of input from people that have experience with the shocks. I won't be moving any of the bypass ports though. I'm sure you can get it dialed in even better, but that's just too much damn work.

Also, does anybody know what special tools you need to take them apart? Somebody mentioned that you need some, but I can't find any info yet on what exactly is needed.
 

·
Vendor
Joined
·
857 Posts
Glamisfan. I applaud your efforts. I think it is great that you can do your own shocks as many others might be able to do as well. I hope you get your car to work much better as everyone should. There is a lot left in your car's ride quality and performance to get. Just keep a few things in mind. You will need $300 of custom shock tools from Fox (only supplier) to take the factory internal bypass apart. Also, they used red lock tight on the bypass tube tension, seal head and they tend to seize up and break your $300 tools so be careful. Valving is the easiest, cheapest thing to do and certainly worth doing. But anyone can do that and call it a valving job as many people do. They are not all created equal. The real improvements in ride quality come from changing the piston to another one with entirely different flow rates. Also, machining the adjuster mechanism so that it flows more fluid will help a ton as well. Change the valving in the adjuster too. You should look into machining the main shaft so that the free bleed can be used after you pass the bypass ports. Also, you should change the bypass port size and locations too. I really don't mind telling you what to look into doing. It is a lot of work and that is what people should understand. For $750 a set, we don't just change the valving. Oh man, that would be sweet and easy for us but no. There is a lot to do and a lot of effort to do it if you really want to get the most out of your shocks. Let me know if you want some direction. I won't tell you what we do but I will tell you good and bad directions to go.

Megadesertdiesle......We don't have canned tunes. We do have a baseline set up that we have arrived at from literally thousands of test drives and hundreds of race team sessions, dune trips, Lucas oil races, BITD and SCORE races that we use as a starting point. From there, we take a lot of time to get your driving style, terrain, accessories, passenger weight, part of the country or world your driving in and make extensive changes to our valving, pistons, oil and spring rates to get a perfect set up for each person if there is actually such a thing. When we work in the shop or on location we take over $50,000 (at 75 cents to $1.90 each) in Valve shims with us. We take over $25,000 worth in pistons and other parts just so we can do what we want every single time differently to match our customers needs. Please don't diminish our efforts to make each customer individually happy with their specific tune with your false statement. Thank you.
 

·
Registered
Joined
·
1,315 Posts
Discussion Starter #12
ST, thank you for the eye opening post. I had no idea about the locktite. Or the adjuster changes, which I wouldn't attempt myself. Sounds like I really need to get a ride in an xpt with your springs and shock work and see if I need to spend that kind of money. My car works pretty damn good now that I have your springs. Hmmmmm.....
 

·
Captain/Paramedic
Joined
·
82 Posts
I should have replied sooner but was at work. The ST tune for the EPT is not a canned tune. The list of questions they ask you is extensive. It includes how you drive where you drive and how much extra weight you are carrying. They want to know your weight is it a 2 or 4 seater? Do you carry a spare tire? Do you carry extra water or fuel? This all goes into them figuring out the suspension set up. On mine when I picked it up they told me it was set loose and to drive it for about 30 minutes easy to get used to it. After that drive it hard and adjust from there. Well a week later I went to Parker for the 425. Added a passenger at 240 lbs and went for a ride. Made a couple of compression adjustments on the shocks and a rear sway bar adjustment and we were hauling ass. There is still a lot of compression adjustment left in the shocks. Couldn't be happier with the set up.
 

·
Registered
Joined
·
45 Posts
Glamisfan. I applaud your efforts. I think it is great that you can do your own shocks as many others might be able to do as well. I hope you get your car to work much better as everyone should. There is a lot left in your car's ride quality and performance to get. Just keep a few things in mind. You will need $300 of custom shock tools from Fox (only supplier) to take the factory internal bypass apart. Also, they used red lock tight on the bypass tube tension, seal head and they tend to seize up and break your $300 tools so be careful. Valving is the easiest, cheapest thing to do and certainly worth doing. But anyone can do that and call it a valving job as many people do. They are not all created equal. The real improvements in ride quality come from changing the piston to another one with entirely different flow rates. Also, machining the adjuster mechanism so that it flows more fluid will help a ton as well. Change the valving in the adjuster too. You should look into machining the main shaft so that the free bleed can be used after you pass the bypass ports. Also, you should change the bypass port size and locations too. I really don't mind telling you what to look into doing. It is a lot of work and that is what people should understand. For $750 a set, we don't just change the valving. Oh man, that would be sweet and easy for us but no. There is a lot to do and a lot of effort to do it if you really want to get the most out of your shocks. Let me know if you want some direction. I won't tell you what we do but I will tell you good and bad directions to go.
I probably just need to pony up the dough....
 

·
Registered
Joined
·
1,855 Posts
ST, thank you for the eye opening post. I had no idea about the locktite. Or the adjuster changes, which I wouldn't attempt myself. Sounds like I really need to get a ride in an xpt with your springs and shock work and see if I need to spend that kind of money. My car works pretty damn good now that I have your springs. Hmmmmm.....


I know it will pain you because you want to do it yourself, but Shock Therapy's work is worth the money. The ride improvement will blow you away and make you fall in love with your car all over again.


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
35 Posts
Back to the original topic anyone have any actual input on doing it yourself?

Sent from my SAMSUNG-SM-N910A using Tapatalk
 

·
Registered
Joined
·
1,315 Posts
Discussion Starter #17
So I bought some Schrader valves to install in my XP turbos internal bypass shocks. Last time I did this was on a maverick, and I had to remove a plastic plug, then an Allen screw, then the rubber pellet, and then drill and tap. This one is different. It looks to be a piece of steel that was pressed in from the inside. It also looks like it's the right size for the tap. Do I just drill from the outside with the proper drill bit and then knock that steel insert out?
 

·
Registered
Joined
·
78 Posts
Shock Therapy did the springs and valving for my XPT while I was at Glamis during Presidents Day weekend. They asked lots of questions about where I ride, how many people in the RZR, and did a great job. Was it expensive? Yes. Was it worth it? Absolutely. It was night and day different. I was running an EVO Stage 3 tune and the shocks were way behind the car. Afterwards, I could lay the wood to her and she soaked up the whoops like a Cadillac.
 

·
Registered
Joined
·
2,115 Posts
So I bought some Schrader valves to install in my XP turbos internal bypass shocks. Last time I did this was on a maverick, and I had to remove a plastic plug, then an Allen screw, then the rubber pellet, and then drill and tap. This one is different. It looks to be a piece of steel that was pressed in from the inside. It also looks like it's the right size for the tap. Do I just drill from the outside with the proper drill bit and then knock that steel insert out?
Yes, i just did the same. Drill through the metal insert and thread for your schrader valve. The schraders i bought had an oring sealing surface that has to be perfectly flat to seal. So make sure to drill and tap with a lathe. Or buy the pipe thread (tapered threads) schraders and you wont have to be so precise.
 
1 - 20 of 69 Posts
Top