'18 Walker XPT Suspension Tuning - Polaris RZR Forum - RZR Forums.net
RZR XP Turbo Discuss the Polaris RZR XP Turbo EPS here!

Reply
 
LinkBack Thread Tools Display Modes
post #1 of 19 Old March 27th, 2018, 10:16 AM Thread Starter
 
dafish's Avatar
 
Member #223617
Join Date: Oct 2017
Posts: 94
Feedback Score: 0 reviews
View dafish's Photo Gallery(0)
'18 Walker XPT Suspension Tuning

Hello all!

I'm about to buy a 2018 XPT Walker Evans (WE), as is a friend of mine. Ride compliance matters to us both, as does having an understanding of what we’re doing and why. In a few posts I'm going to ask vendors, aside from ST, to PM me their prices on some springs. Or reply here in the thread. Vendor preference.

Before I do that I'm going to share for others what information I've accumulated after a fair bit of Google-fu (all relative to the ’18 WE XPT). Feel free to correct me if you think I'm wrong, or skip to the next part where I show my ignorance and ask for your help.

Thanks in advance to all!

D

Last edited by dafish; March 27th, 2018 at 12:50 PM.
dafish is online now  
Sponsored Links
Advertisement
 
post #2 of 19 Old March 27th, 2018, 10:18 AM Thread Starter
 
dafish's Avatar
 
Member #223617
Join Date: Oct 2017
Posts: 94
Feedback Score: 0 reviews
View dafish's Photo Gallery(0)
Re: '18 Walker XPT Suspension Tuning

OK, facts as I know them (and open to debate):


1) Drivers feel, front and rear, a single rate spring as both tenders are usually coil bound.
a. The front is under-sprung, while the rear is over-sprung.
b. The 2018 XPT has newer springs packages for this year.
2) Per WE, the 2018 XPT front shocks have revised, reputedly better, valving.
a. ST tells me they are seeing an uptick in failure rates on the ’18 fronts, reason unknown.

Factory Spring information:
1) OEM (per Polaris online parts manual)
Front
Tender 300-prog, 3.75", 3.0" id (progressive rate unknown)
Primary 260lbs, 12.75", 3.0"id
Rear
Tender Prog, 5.05", 3.0" id (rate again unknown)
Primary 225lb, 15.75" 3.0" id

2) Eibach's stage 2 kits is:
Front
Tender 250lb, 6", 3.0"
Primary 300lb, 10", 3.0"
Rear
Tender 200lb, 10", 3.0"
Primary 250lb, 18" (also reported to be 14")

3) Eibach's stage 3 kits is:
Front
Tender 250lb, 6", 3.0" id
Primary 300lb, 10", 3.0"id
Rear
Tender 200lb, 10"
Primary 300lb, 18" (also reported to be 14")

4) Walkers Spring kit
Front
Tender 200lb, 6"
Primary 300lb, 12"
Rear
Tender 200lb, 10"
Primary 200lb, 16"

It seems total uncompressed spring length range can be in the range of:
Front: 14” through 19”
Rear: 21” through 28” (I suspect rear primary must be at least 14”)

For those that are considering their own serial shock package creation, the formula is:
1/k(sum) = (1/k1)+ (1/K2) + …..
or
For dual spring you can use (k1xk2)/(k1+k2).
A triple rate seem difficult to make fit. At some point this is valvings job to control

Last edited by dafish; September 11th, 2019 at 01:32 AM. Reason: Eichbach now has a stage 3 kits
dafish is online now  
post #3 of 19 Old March 27th, 2018, 10:20 AM Thread Starter
 
dafish's Avatar
 
Member #223617
Join Date: Oct 2017
Posts: 94
Feedback Score: 0 reviews
View dafish's Photo Gallery(0)
Re: '18 Walker XPT Suspension Tuning

Hm.. I see it doesn't like outlines... darn.
dafish is online now  
Sponsored Links
Advertisement
 
post #4 of 19 Old March 27th, 2018, 10:24 AM Thread Starter
 
dafish's Avatar
 
Member #223617
Join Date: Oct 2017
Posts: 94
Feedback Score: 0 reviews
View dafish's Photo Gallery(0)
Re: '18 Walker XPT Suspension Tuning

My preliminary roadmap for changes is next, and this is where I need all the help I can get. A disclaimer: I've a lot of respect for Eibach and Walker for being pretty open with information, so my purchases will all center around supporting those that have supported us.

Suspension Roadmap:

Rear:
1) Replace the rear tender with a 200lb 10” Eibach and back out the compression damping quite a bit, looking for sway and bottoming vs. ride harshness and a rear crossover ring.

2) If bottoming, or too much sway after crossover, and compression is where it’s wanted, replace the bottom with a 300Lb Eibach at 14 or 16” inch or re-valve (Revalve first?).

3) Still not the ride desired? Now send the shocks to be revalved? Or is it the fronts?

4) Got the compliance right except for sway and don’t want to lose compliance? Stiffer sway bar (expect to lose some compliance anyway. Walker links?)
a. Which one first? Rear has the most mass and has the most tire.

Front:
1) Probably replace the front tenders with a 200Lb 6” Eibach. Skip the crossovers, let’s see if it coil binds soon enough. But talk to WE about the 2.5” first. Replacing may be the right move!

Front Replacement Options:
1) WE has a 2.5" shocks with " shafts, crossovers and Eibach springs that should be obtainable for a fairly reasonable cost.
2) The next step up, the Velocity, offers what I believe is damping based on velocity. Prolly overkill.

Purpose Considerations:

Use:

Fire roads, woods, trails etc. Occasional low speed complex/ high difficulty terrain, but not often. No dunes (darn it).

Passenger load:
240lbs

Options:
Front and rear bumpers, front winch (30lbs), and 25lbs of “stuff” in back. 29” Crawler XG’s on stock rims.

Last edited by dafish; March 27th, 2018 at 12:52 PM.
dafish is online now  
post #5 of 19 Old March 27th, 2018, 10:25 AM Thread Starter
 
dafish's Avatar
 
Member #223617
Join Date: Oct 2017
Posts: 94
Feedback Score: 0 reviews
View dafish's Photo Gallery(0)
Re: '18 Walker XPT Suspension Tuning

Huh... Partial double post. Odd.. Deleted.

Last edited by dafish; March 27th, 2018 at 12:54 PM.
dafish is online now  
post #6 of 19 Old March 27th, 2018, 10:32 AM Thread Starter
 
dafish's Avatar
 
Member #223617
Join Date: Oct 2017
Posts: 94
Feedback Score: 0 reviews
View dafish's Photo Gallery(0)
Re: '18 Walker XPT Suspension Tuning

And now, as if I haven't already proved I don't know anything, are my questions:

1) Anybody think the roadmap above is wrong?

2) If you're a reseller would you please reply, or PM me, costs of Eibach tender springs for front and rear? What spring rates you would suggest as well as qty (2) 0600.300.0200, and (2) 1000.300.0200 please?

3) Given a 6” 200lb front tender over the OEM 12.75” 260lb primary, it seems like that would have in the area of 2 — 2.5” of shaft travel sitting in the ground) before coil bind. Why bother with a crossover here?

4) In front, why isn’t a 8” tender over a 10” primary used so there is more “combined” rate up front? Nobody does, so there must be a reason! Too much dive and/or sway? Not enough thread distance?

5) Can the 12.75” 260lb front primary be used as the rear primary? This over a 200lb 10” tender. Assuming so, would the threads come down far enough to allow a reasonable cross-over point?
(That's a "Not too likely". The primary would be likely fall off the body, as the shaft travel itself is 12". It might work today, but if the spring sagged at all over time it would be trouble)

6) Does anybody other than Shock Therapy make a quiet version of a crossover ring? I'll buy them if I've no good option, but I'd prefer not too.

Any insights or comments are appreciated. And if nothing else perhaps the information above helps other thinking about the Walker Evans version and ways to improve them in cost effective steps.

All the best,
D

Last edited by dafish; March 30th, 2018 at 11:59 AM.
dafish is online now  
post #7 of 19 Old March 27th, 2018, 10:46 AM
 
FRAZR's Avatar
 
My RZR: XPT4 Velocity
Member #82174
Join Date: Jun 2015
Location: Arizona
Posts: 1,106
Feedback Score: 0 reviews
View FRAZR's Photo Gallery(0)
Re: '18 Walker XPT Suspension Tuning

I've got a nice set of Front 2.5" Walkers w/ ST Tune, springs and silent crossovers if you're interested pm me. I've also got an extra set of 2.5" silent crossovers that I'd throw in. Thanks for posting the information. Looks like you've done your homework.
Attached Thumbnails
Click image for larger version

Name:	IMG_1384.JPG
Views:	95
Size:	154.9 KB
ID:	528642  
FRAZR is offline  
post #8 of 19 Old March 27th, 2018, 10:52 AM
 
shortdeck's Avatar
 
Member #170641
Join Date: Nov 2016
Posts: 39
Feedback Score: 0 reviews
View shortdeck's Photo Gallery(0)
Re: '18 Walker XPT Suspension Tuning

Installing Eibach springs will improve any car. IMO it's money well spent. I myself did it and ordered springs through Kartek. In the front 350 over 350. In the rear 200 over 300. The front is a little stiff, I can reduce some spring rate on the front upper if I wanted. You can order the springs individually if you on a budget and see how it helps.


Sent from my iPhone using Tapatalk
shortdeck is offline  
post #9 of 19 Old March 30th, 2018, 12:03 PM Thread Starter
 
dafish's Avatar
 
Member #223617
Join Date: Oct 2017
Posts: 94
Feedback Score: 0 reviews
View dafish's Photo Gallery(0)
Re: '18 Walker XPT Suspension Tuning

Thank you Frazr. PM sent sir.

Not a lot of folks chiming in. I didn't read it all, but there is a simply huge thread (30, maybe even 50 pages) of folks working on the 900 springs. Surely I'm not the only one wanting to line up some hard data for the XPT folks.

At present I'm still thinking I'm going to start with new tenders front and rear. 200lbs both, in 6" and 10" respectively. Although I need to get to TN and go pick up the new ride first, and I'll certainly consider Frazrs shocks.

BTW, those tenders might be light. If I was thinking dunes and big G outs I'd be going 250 on the front, 225 on the back for tenders, and thinking 300 in the rear primary.

Anybody here a Nascar fan? If so, do you recall the days of using spring rubbers to tighten up the car by increasing coil rate? How come I've read exactly zero on here about folks using spring rubbers or stiffeners to increase spring rate to see what they liked? Sure seems like a reasonable way to test what a change does.

Anybody know the math to that? I know if you cut a spring in half you double it's rate. If you insert a spring bumper aren't we just locking out one turn? So on a 200lb spring with 5 turns, is that spring now a 250lb effective rate? (200x5/4)

Seems like an easy way to be taking stock springs and seeing what we like without having to buy lots and/or ship them back and forth...

Thoughts?

Thanks!
D
dafish is online now  
post #10 of 19 Old March 30th, 2018, 12:57 PM
 
mark5193's Avatar
 
First Name: mark
Member #1018
Join Date: Jan 2008
Location: olympia, wa
Posts: 5,412
Feedback Score: 11 reviews
View mark5193's Photo Gallery(5)
Re: '18 Walker XPT Suspension Tuning

bump
mark5193 is offline  
post #11 of 19 Old April 2nd, 2018, 08:09 AM Thread Starter
 
dafish's Avatar
 
Member #223617
Join Date: Oct 2017
Posts: 94
Feedback Score: 0 reviews
View dafish's Photo Gallery(0)
Re: '18 Walker XPT Suspension Tuning

Partial double post. huh...

Last edited by dafish; September 12th, 2019 at 02:40 PM. Reason: Another partial double post. Wierd
dafish is online now  
post #12 of 19 Old April 2nd, 2018, 08:26 AM Thread Starter
 
dafish's Avatar
 
Member #223617
Join Date: Oct 2017
Posts: 94
Feedback Score: 0 reviews
View dafish's Photo Gallery(0)
Re: '18 Walker XPT Suspension Tuning

More answers for others that may search one day:

Yes, spring rubbers or "helpers" can be of real value. But remember, these are coilovers, and the spacing between the shock body is pretty minimal. Personally I think the best option is an insert that follows the wrap of the coil, and that it be placed at the bottom the coil. I'm thinking at the same place as the shaft bump stop.

If there was enough space at the shock body at the spacer this too might work. Seems likely there isn't enough room there though, but it would sure be sweet if it did. Maybe a tie-wrap would help.

So the math behind this turn out to be pretty simply: Rate is the reciprocal of the effective coils.

If we cut a spring in half we all know it would double the rate. The reciprocal of 1/2 is 2/1, with simplifies to X2. Perfect, it seems the math works. So now an example pertinent to the XPT:

Lets are an 8 coils spring rated at 225lbs. Lets block out one coil, leaving 7 effective, and multiple the initial rate by the new reciprocal of 8/7. Lets call that 260 (It's 257 and change). 1.5 coil turns would be 277. Darn, I like that rate, and I hope this works.

Spring spacers at Farm and Fleet are $6 each.

Full disclosure: Spring rubbers have their own rate unless they are rigid. This can affect the results, and in racing circles rubbers are rate in pounds themselves. Given the option I would be taking "firm", or "hard" rubbers so I was getting about what I expected.

As with all these posts, I hope this helps others as they consider their spring decisions, and I hope you reward Eibach and Walker with your business, for they're the ones openly telling us what they recommend.

Props to all,
D
dafish is online now  
post #13 of 19 Old September 12th, 2019, 02:56 PM Thread Starter
 
dafish's Avatar
 
Member #223617
Join Date: Oct 2017
Posts: 94
Feedback Score: 0 reviews
View dafish's Photo Gallery(0)
Re: '18 Walker XPT Suspension Tuning

Well, I've crunched the front of the XPT (darn deer) and now need to replace upper and lower A-arms. Since I have to take them apart I'm going to do deal with springs too. And to stay out of my wives doghouse I need to keep a close on on the spend too.

Ive ordered:

(2) 10 300lb and 325lb front primarys, and (2) 8 250Lb front tenders.
(2) 10 200lb as rear tenders
$119

(4) SDI Crossover rings
$115

SuperATV A-arms, reuse ball joints
$372

$606 to my door. Not bad given the severity of the fudge up. Ill need to deal with the bend in my front bumper yet, and I probably should have brought in a set of 300lb rear primaries just in case, but if Im unhappy I can use a spring spacer to increase the rate of the lower rear primary as a taste.

Still remaining:
Can I live with the valving?
Which of the front primaries do I try first?
What else might have got hurt on the hit?

Given I've 80lbs of accessories on the nose I'm thinking I might use the 325 primaries...
dafish is online now  
post #14 of 19 Old September 12th, 2019, 09:31 PM
 
SNWMBL's Avatar
 
First Name: Caleb
Member #207521
Join Date: Jul 2017
Location: Alaska
Posts: 367
Feedback Score: 0 reviews
View SNWMBL's Photo Gallery(0)
Re: '18 Walker XPT Suspension Tuning

My knowledge is limited but as far as the front tender springs go, Im not sure why everyone uses 6. I currently have 6 tenders over 10 mains. My tender collapsed length is 2.20(per Eibach) so I have my crossover rings set about 2.30 below the top of the spring. With 1-7/8 of preload(to get proper height) and the rzr sitting on the ground and settled, I have less than 1 from the plastic spring divider to the crossover. For me there doesnt seem to be much point in the crossover, I just left in to keep the spring from going into full coil bind.

Using Foxes chart to calculate the crossover location I cant even get close to it. It would seem to me that an 8 front tender would be much more useful and allow for more crossover adjustment.

I plan on getting 2.5 WE front shocks from Pound Sand this winter or Id buy new tenders.

2017 RZR XP4 1000
SNWMBL is online now  
post #15 of 19 Old September 12th, 2019, 11:19 PM Thread Starter
 
dafish's Avatar
 
Member #223617
Join Date: Oct 2017
Posts: 94
Feedback Score: 0 reviews
View dafish's Photo Gallery(0)
Re: '18 Walker XPT Suspension Tuning

Its the spring divider. It must be projecting something like 2 above the bottom of the tender. Can it be inverted or shortened to give you more travel? You can tune your expectation on the cheap here. Heck, cut it.

Ive done the math, I dont think 6 is unreasonable, but the divider is the controlling component. Im relatively sure divider height is how some vendors (I dont name them because I dont agree with them) are using 6 tenders. Mind you I suppose its an easy and cheap way to market a consistent canned product. Im just more of a but I want to be able to tune it my way kind of guy.

Anyway, yes, 8 should take divider height out of the way and give more flexibility. Its not like the spring is any more expensive. Although it may need some compression to be installed too, and thats also part of why some vendors like the 6 tender. Easier for customers to install means less headache for them. But tuning it means taking the shock and spring off and changing the divider!

Thinking more about this, I sort of get why some vendors do this. Its not for me, but there are a lot of guys (and gals) out there dont think too critically, and more that arent handy enough to want to tune it. For them a canned answer would be easier.

I just think youd have been better served with maybe to maybe a shorter divider.

Moving on, regarding crossover height, I was planning on experimenting. Im going to start out with trying 3.5 of luxury wheel travel from race sag. Front shock shaft to wheel travel ratio is 2.46:1, and so thats 1.4 inches of crossover between the divider and bottom of the crossover ring. Even then I fear I may find that too soft for the kind of tossing around of this thing that I do.

On the other hand you may have noticed Im a bit heavy on both the tender and the primary spring rates. All part of the plan. My hope is to be able to carry a bit more combined (soft) travel (distance) before transition to the heavy rate. The trade-off for longer travel is a little stiffer cushion and a little stiffer final rate.

And of course the concern is I may be over-tuning springs to correct what is really a shock valving domain. Well know if I end up feeling Im over-damped and under rebound.

BTW,
- Polaris specs claim 16" of wheel travel and 20" of "Usable travel overall"
- Actual shaft travel front) looks to be 6.5"
In wheel travel terms that's a 2.46 ratio (to one inch).

All of which means your 1of tender shaft travel is about 2.5 of wheel travel. Im interested Do you find that too little? What do you wish you had for wheel travel? What is your riding stye? What are the part numbers stamped on the front springs you have now?

Disclaimer: I dont know anything, so use any of this at your own peril.

Thanks,
D
dafish is online now  
Reply

Tags
spring rate , springs , walker evans , weight , xpt

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Polaris RZR Forum - RZR Forums.net forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
XPT Walker Color dafish RZR XP Turbo 21 March 21st, 2018 02:37 PM
Questions about tuning - 17 XPT KANE RZR XP Turbo 52 October 13th, 2017 10:03 AM
XPT stock suspension limitations Lennyg3 RZR XP Suspension 4 July 15th, 2017 07:33 PM
2017 XPT suspension American Rock Rods Polaris RZR Parts For Sale 10 June 18th, 2017 08:18 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome