• Don't miss out on all the fun! Register on our forums to post and have added features! Membership levels include a FREE membership tier.

Khaos Rails on a Regular Pro RMK

die hard poo

Well-known member
Lifetime Membership
Apr 10, 2008
1,177
796
113
37
Kenai, AK
Hey I just want to confirm that a person can bolt on Khaos rails onto a stock Pro RMK sled and everything will work right. I have read that they are pretty much just an Assault rail profile but I want to make sure the rails won't come in contact with the stock drivers. And just to clarify, this is just the rail, no front arm or shock changes. Can it be ran in the top hole in the tunnel or does it need to go into the lower one like an Assault?
Thanks in advance
 

IceAge Performance

Well-known member
Premium Member
Nov 26, 2007
438
779
93
Gallatin Gateway, MT
The rails bolt up totally fine and will not impact or affect the drivers in any ways. You can run them in the upper hole. The only thing you would need to verify is the longer Khaos FTS may bottom out before the front arm hits the lower bump stops on the RMK rail (less bend means lower bump stop height) Otherwise the limiter is a slight bit longer then the RMK but nothing that will create issues.
 

die hard poo

Well-known member
Lifetime Membership
Apr 10, 2008
1,177
796
113
37
Kenai, AK
We will be using the stock Pro RMK FTS and torque arm (the whole rear suspension onto the khoas rails) so it may cause a bit less travel due to the bump stop being closer right?
 

Wheel House Motorsports

Well-known member
Lifetime Membership
Nov 27, 2007
29,933
5,968
113
34
SW MT
We will be using the stock Pro RMK FTS and torque arm (the whole rear suspension onto the khoas rails) so it may cause a bit less travel due to the bump stop being closer right?
I haven't bolted one up and cycled the front shock. You end up with basically the normal RMK travel. Issue might be because the shock is longer but now being forced into a lower portion of the stroke.

Rail tips are lower on rmk (gentle bend) which pulls the limiter strap down approx 5/8". It also pulls the bump stops down as the rail has the shallower bend. So the usable travel is virtually the same on either rail profile. Only just risking bottoming the longer khaos FTS when putting on RMK rails since now the arm is traveling a bit lower in the stroke before it bottoms on the RMK rail.
 

die hard poo

Well-known member
Lifetime Membership
Apr 10, 2008
1,177
796
113
37
Kenai, AK
So I may not be explaining what we are doing effectively, we are sticking Khaos rails onto a PRO RMK suspesion. The only Khaos component is the rails.

The intent is to create a more playful PRO RMK by using the Khaos rail only. This should then "raise" the limiter strap since the rails are tipped up more and with the PRO RMK shock being used, it may cause the travel to be reduced some since the bump stop will be closer to the torque arm, correct?
 

Wheel House Motorsports

Well-known member
Lifetime Membership
Nov 27, 2007
29,933
5,968
113
34
SW MT
So I may not be explaining what we are doing effectively, we are sticking Khaos rails onto a PRO RMK suspesion. The only Khaos component is the rails.

The intent is to create a more playful PRO RMK by using the Khaos rail only. This should then "raise" the limiter strap since the rails are tipped up more and with the PRO RMK shock being used, it may cause the travel to be reduced some since the bump stop will be closer to the torque arm, correct?

OK, so your going to run into the opposite problem now. The stock RMK FTS only has about 1/8" of preload on it. When you install the khaos rails on it, your going to be moving the limiter strap up now 5/8" so your shock will lock open WELL before the limiter does anything. So to manage this you have to tighten limiter a bit to maintain some preload and not damage the shock. So alternatively you could mount the skid in the lower tunnel hole and you made yourself an assault. Less FTS travel, more aggressive approach angle etc. Also because its a much different use of the RMK shocks you end up with almost no ski pressure and minimal steering ability.

Right now there are a few companies looking at a kit to build what you want but the RMK shock just isn't going to allow packaging to create a Khaos geometry.
 

die hard poo

Well-known member
Lifetime Membership
Apr 10, 2008
1,177
796
113
37
Kenai, AK
Ok well we may try a couple different combos. If needed, we will shorten the limiter to ensure the shock isn't stressed too hard. And we will play with running the skid in the stock hole and maybe try in the lower hole too.
 
R
Mar 9, 2017
308
72
28
stillwater MN
Just thinking out loud here... Could you move the mounting location of the center shock on the rail fwd to the next pre drilled hole?? If i remember it is 3/4 or inch fwd ... This would stand the shock up more and should create more travel? I would try and cycle suspension with no spring on shock to see what happens..
 
R
Mar 9, 2017
308
72
28
stillwater MN
I should not of said more travel,,, it will create more downward travel by moving fwd, still may have to play with bump stops but, I would move it fwd and cycle suspension with no spring on shock.. You may get what your looking for,,
 

Killer Time Racing

Well-known member
Lifetime Membership
Feb 12, 2008
996
223
43
49
Lower Michigan
Isn't your rail idea going to limit playfulness?? If you suck up the limiter you will be pulling the rails up and creating more ski pressure. I've bottomed many shocks with horrific results !!!

Just make sure you have a extra track and FTS and all should be good !!
 

die hard poo

Well-known member
Lifetime Membership
Apr 10, 2008
1,177
796
113
37
Kenai, AK
After looking into this more, it should be fine with stock PRO RMK suspension components. Basically we're turning the rear skid into an Assault rear skid. From what I understand the rail profile is simply an Assault rail. And the Assault and PRO RMK use the same FTS length (different spring but same length shock), same front torque arm, and limiter strap. We will go ahead and just keep everything else the same and install the rails and see what happens. It won't be quite as setup as the Khaos since it has a slightly longer FTS and torque arm but overall should be a good in between.
 

off trail mike

Well-known member
Lifetime Membership
May 31, 2011
318
129
43
New Brunswick, Canada
So the stock RMK FTS is 11.75" eye to eye, and cant remember the stroke. Wonder what the Khaos FTS is eye to eye? Seems to me it would be the same with slightly shorter stroke on account of the increase tip up angle in the rail and hitting the rubber stopper more quickly as mentioned above, but if they tried to increase travel by adding shock length, it could be very different. There are other FTS shocks out there in the 12-13 inch length that might work too.

Regardless, someone should measure and compare RMK and Khaos shock lengths. Small changes to angle of attack (rail tip up) cause big changes to handling and playfullness BUT push it to far you'll get a sled that trenches easily... Summits are very playful, but trench out more easily as well.

Hopefully Polaris has figured out that balance on the Khaos.
 

die hard poo

Well-known member
Lifetime Membership
Apr 10, 2008
1,177
796
113
37
Kenai, AK
So I had the chance to throw the khaos rails onto a stock Pro RMK using all the stock Pro RMK suspension components.

Attached is a picture showing the difference on the front rail tip up. Not a huge change but it does effectively change the limiter strap length on the stock Pro RMK (by having the tip raised, it raises the lower limiter strap cross shaft height in relation to the upper Front torque arm).

As far as the difference between the length of the Front Torque Arm, I measure both the Khaos and the RMK and they measured center to center the same, approximately 17 3/16". The front track shock length on a Khaos is 12" ctc and the RMK is 11 3/4". I forgot to measure the limiter strap length on each though... We will see if just changing the rail will make any difference on the regular Pro RMK in the playfulness or not.

rails.jpg
 

cvcustoms

#getsomegetthere
Lifetime Membership
Sep 10, 2018
195
200
43
www.cvcustoms.com
Raptor Shocks has a kit you can call and order that comes with a new eyelet for the factory Pro RMK shock and the limiter straps for $100 I believe... don’t quote me in the price... it is not in the website yet so you have to call.


850 & 800 PIDD Cables
www.cvcustoms.com
Get Some Get There
 

frntflp

Well-known member
Lifetime Membership
Nov 29, 2007
403
150
43
Plymouth, MN
Could gas shock repair lengthen your stock rmk shock and the. add the kaos limiter strap . Done?

I would think so. Any good shock shop should be able to install a slightly longer shaft - then the longer limiter strap.
 
Last edited:

Sheetmetalfab

Well-known member
Lifetime Membership
Oct 5, 2010
7,910
6,670
113
……..
I’m going this route. Khaos rails on my 163 RMK.
Trying to eliminate the rail tip wear issue running the 3” PC.View attachment 335231

I have no wear on my rail tips with the 3” PC track.

(Probably the MTNTK bulletproof anti stab kit doing that though......)

Slightly oversized wheels.
Beefy 7/16” diameter hardware.
Solid 1” diameter shaft.

Smooth and fast with a tight track.
 
Premium Features