155 ASSAULT COMPARED TO 155 RMK RAILS... DIFFERENCES WITH PHOTOS

[milehighassassin]

I assume Polaris learned a lesson from the IQ Assault. They had to do a recall on the Assault rails because they were having track stabbing issue.

Eric, do you know if they tips are different as well? I know that was the fix for the stabbing issue on the IQ.

 

[AkLogan]

notice the cross shaft between the front and real arms. this is where mine bent and another friends was starting to bend.

 

[milehighassassin]

notice the cross shaft between the front and real arms. this is where mine bent and another friends was starting to bend.

Do you have an RMK or Assault?

 

[POLZIN]

The purpose of this thread, for me, was to simply show that the Assault rails are different, and to clarify what those differences are.

The Assault rails are turned up in the front simply to take into consideration the angle of the track/rail interface with the Rails dropped lower which causes a taller attack angle.. Using the RMK rails on the Assault will casuse more friction and Hyfax wear on at the front section.

The drive shaft and drivers are the same and in the positon as the RMK. The rear suspension is the same including the non adjustable limiter straps. The Assault suspension has the same travel as the RMK.

You could use the Assault rails on the RMK... but not vise versa UNLESS you moved the front suspension to the top holes that you drilled all the way through on the tunnel of the Assault





...

So its clear there should not be any trouble using RMK/ICE AGE rails on the Assualts so long as the front skid mount has been moved to the upper Position ( RMK GEOMETRY) .

That is correct yes ?

 

[WyoPro]

MH, just for the sake of argument have you had both sets of rails with all suspension components stripped off and taken some measurements? The perspective in both photos are taken from different angles, not sure you can say much from a geometry standpoint on that alone....

 

[AkLogan]

I have a rmk and the bowed out wherethat cross bar is and then they bent up from there back.

 

[gman086]

I have a rmk and the bowed out wherethat cross bar is and then they bent up from there back.

Doesn't Ice Age make some rail stiffeners that go there? Would seem like a no-brainer instead of their new Bomber rails if you go big.

Have FUN!

G MAN

 

[Rudy198]

correct me if i'm wrong..i have a 012 Assault so by lowering the front mounting bolt it will help the sled get up on top of the snow better....If that is true what do i lose by moving it down?if anything..

I have read guys say it does make the sled ride more like a Pro,just the Assault is a bit wider and a touch heavier,plus i went with the 5.1 track rather than the comp.

 

[WyoPro]

correct me if i'm wrong..i have a 012 Assault so by lowering the front mounting bolt it will help the sled get up on top of the snow better....If that is true what do i lose by moving it down?if anything..

I have read guys say it does make the sled ride more like a Pro,just the Assault is a bit wider and a touch heavier,plus i went with the 5.1 track rather than the comp.

It's all about ski pressure and the way that the skid transfers. Moving the front mounting location down to the stock Assault location will give you less ski pressure. Your 012 Assault should already be in the lower hole (you won't see the location of any other hole than this, there are pre-marked locations on inside of tunnel to drill out other mounting locations...3-4? been awhile)

It's a complicated dynamic because moving this location affects the way the skid transfers as well as the way your front suspension will react. Simply put, theoretically the regular RMK will get up on top of the snow and climb better in deep powder with the upper mounting location as compared to the Assaults lower mounting location assuming same clutching and tracks, etc...

That being said, I rode my Assault in the lower location 95% of the time and the difference was negligable between a stock 155 RMK with the same tracks and IMO the lower mounting location of the Assault had a better fun factor due to the lesser ski pressure...

 

[Rudy198]

does anyone have a picture of where the stock one was and then lowered,just wanna make sure it'll be done right,Thanks

 

[AkLogan]

Doesn't Ice Age make some rail stiffeners that go there? Would seem like a no-brainer instead of their new Bomber rails if you go big.

Have FUN!

G MAN

the ice age rail stifferns that they sold me were just the polaris ones like those on the IQR but they were 11.50 inchs long insted of 7. i have the part number at home.

 

[mountainhorse]

Logan,

Did you install those on the stock PRO RMK Rails?

Got pix?

 

[mountainhorse]

Polzen.... YES.

WyoPRO is right on with his presentation... The dynamics of spring preload, position in the chassis and many other factors dictate how the sled will react.

I have had the rails next to each other... they are identical except for the front turned up section of the rail. I'll see if I can snap a photo of this with them next to each other as the show season fires up.

All of this is assuming that the wider front suspension and longer shocks of the assault puts the skis at the same height in relationship to the sled... Which may not be true. I don't have the answer to this one... Does anyone else out there have this info.... with first hand experience? (Pic below of what I'm talking about, not to scale NOR representing any thoughts of what the actual measurement is)

We may be shooting ourselves in the foot by assuming that this position is the same on the RMK and Assaults.

The Assault has a steeper approach angle of the track... which is why the rail tips are turned up more than the RMK. This approach angle directly affects how the sled will get up on top of the snow. You can see how much extra this is by looking at the drastic diff in the position of the rear idler/track-tension adjuster on the rear. (the Comp and powder tracks are molded on the same drum)

How compliant the front track shock is also has a huge effect on this. The RMK has a 150 lb spring on the front track shock with softer valving than the Assault front track shock with the 180 lb spring.

.

 

[AkLogan]

no i didnt i wasnt realy looking all that hard to find them for stock rails. By the time i reliezed that mine were bent it was already to late to save them. ill get some pics tonight or tomorrow of the brackets on the ice age rails.

 

[Freeride1]

I like the idea of less ski pressure making the Assault more fun to ride. A friend of mine mentioned that about his 2010 Assault but didn't know why it felt better.

Could the RMK be run in the lower front hole with anti stab wheels safely?

That is a big improvement to any M-series to run the lower front holes in the tunnel. Takes so much weight off the skis. I would like to see what it is like on my Polaris.

 

[AkLogan]

with my skid in the stock location i didnt think it had enuf ski pressure. on a pro 155.

 

[mountainhorse]

Here is my OPINION

Again... to assume that the Assault has the same ski bolt location in relation to the chassis may not be a good idea when making the comparison.

It is quite possible that the lower swing arm mounting in the Assault also takes into account a possible lower ski pivot bolt location in relation to it.

My gut (and nothing else to be honest here) tells me that swapping things around may change more than you are planning on.

Ski pressure is also affected by FTS preload and spring force.

.

 

[Freeride1]

That is interesting. There is an Assault next to my Pro RMK in the showroom right now. I am going to measure the groundclearance under the belly pan to see if there is a difference. If there is that would definately support that theory of the ski pivot point being lower like you said MH.

 

[RMK-King]

That is interesting. There is an Assault next to my Pro RMK in the showroom right now. I am going to measure the groundclearance under the belly pan to see if there is a difference. If there is that would definately support that theory of the ski pivot point being lower like you said MH.

The Assault front suspension has a inch more travel then the Pro, so measuring under the belly pan will not be accurate.

 

[Freeride1]

I never knew that about the Assault front suspension. It is logical it has more travel with the longer A-arms though. That would help explain the added height up front.