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skis_n_skid
04-11-2009, 02:26 PM
We have an XLT SP with x12 suspension and an XLT SKS with 136 x10 suspension. The x12 is a boat anchor in anything more than a foot of snow. This summer I'm going to long track both of them to 144. Optimally, I would like to find a couple of Edge 144 skids. If I only buy one skid, I'll just put 136-144 extensions on the x10. I might even replace the x12 with a 136 skid and put extension on that one too.

I was just reading a thread about coupled vs uncoupled suspensions. Is it accurate to say that an uncoupled suspension is better for deep snow than a coupled suspension (since the angle of the skid can change to conform to the ground better)?

I was just reading that an Edge 136 suspension is coupled, and you have to get a 144 to get an uncoupled Edge suspension? Is a 136 xtra lite suspension uncoupled? What about a 136 Pro X? Would a 136 xtra 10 suspension work better in deep snow than a 136 Edge since the xtra 10 is uncoupled and the Edge is coupled?

What suspension would work the best in a wedge chassis for fairly deep snow? I'll be using 8 tooth drivers with 1.75 track. I don't want to try to high mark any big hills, I just want to be able to go off trail and be able to trudge through some fairly deep snow.

550iq
04-11-2009, 09:12 PM
I had an XLT SP (97 model) and installed a 133 (X-12 SKS) rail and 136 x 1.25 track, and built a small rail extension to make it work. Do not go any longer than 136 on the X-12 or you will slam the track into the back of the tunnel. Concerning the X-10, Holz's initial rear skid bolted rignt in. Their torque arms and an X-10 136 rail. My recommedation is to leave the X-12 alone and ride the trails.

Try to work with the X-10. Bolt on 136 rails, take out the rear coupler blocks, and see how it goes. Try Holz and see if they have some older rear skids left. The Indy Lite skid is not coupled and will bolt in with some different torque arm to tunnel locations.

I would recommend against 121 to 136 rail extensions - a quite long moment arm working against the four mounting bolts.

Coupled suspensions are designed to thrust the machine forward with minimal weight transfer-minimal ski lift, just the opposite with the uncoupled suspension.

Lots of blather here, hope it makes some sense. Cheers.

MARV1
04-12-2009, 12:37 PM
136 Edge RMK skids are uncoupled. There are some in swap or tracksusa. Plenty of take off suspension components in swap and maybe ebay. If you want a more serious deep snow XLT then this is the route you should take, don't get or extend the coupled skids. I have the same thoughts for this summer, buy an XLT and extend it.

ivar
04-13-2009, 06:26 PM
I was just reading that an Edge 136 suspension is coupled, and you have to get a 144 to get an uncoupled Edge suspension? Is a 136 xtra lite suspension uncoupled? What about a 136 Pro X? Would a 136 xtra 10 suspension work better in deep snow than a 136 Edge since the xtra 10 is uncoupled and the Edge is coupled?

Xtra-10 is also fully coupled, like the edge and Pro-x skids. The uncoupled 144" edge skids you're refering to is used in the edge + IQ RMK/switchbacks.

I would recommend against 121 to 136 rail extensions - a quite long moment arm working against the four mounting bolts.
Got 4 seasons and a couple 1000 miles on the TracksUSA 121-136" extensions on my 02 XC800, no issues whatsoever.

For deep snow, the skids approach angle is just as important as whether its coupled/uncoupled. A nice, low approach angle will better keep the sled on top of the snow, while a skid/chassis with a steep approach angle will trench much more. And this is what hurts the X-12 most in the deep.

IMO the cheapest would probably be to find a 136" Xtra-10 skid to put in the xtra-12 sled, then find some 136-144 extensions for them.

Irace
04-20-2009, 07:29 PM
I've run 121" to 136" extentions on my last 3 sleds, all were coupled. Absolutely no issues, I ride hard too. MOST extentions fit into where your idlers previosly were to add strength. I use more than 4 bolts too, drill a couple extra.

skis_n_skid
05-01-2009, 12:26 PM
My recommedation is to leave the X-12 alone and ride the trails.

The whole point of this project is to be able to get off the trails more and be able to handle deeper snow. :D

Try to work with the X-10. Bolt on 136 rails, take out the rear coupler blocks, and see how it goes.

The x-10 I have is a 136.

Xtra-10 is also fully coupled, like the edge and Pro-x skids. The uncoupled 144" edge skids you're refering to is used in the edge + IQ RMK/switchbacks.

The 136 x-10 is not coupled, and as I have found out, the RMK 136 edge suspension (as well as the x-lite) are not coupled either. They all have pivot arms on the rear torque arms that allow the skid angle to change independently of the tunnel

IMO the cheapest would probably be to find a 136" Xtra-10 skid to put in the xtra-12 sled, then find some 136-144 extensions for them.

I considered doing exactly that for a while. 136 x-10 skids are readily available for cheap on ebay. But if I put a x-10 skid on with a x-12 front suspension I think I would need to lower the front end some how. I also like the idea of having more travel with a x-lite or edge suspension. I figured since I have to move mounting locations no matter what skid I put in, I might as well keep an eye out for a deal on a 136/144 x-lite or a 136/144 edge. Worst case scenario I end up settling for a 136 x-10.

skis_n_skid
05-01-2009, 12:53 PM
Thanks to everyone for all the input. :beer;:beer;

136 Edge RMK skids are uncoupled. There are some in swap or tracksusa. Plenty of take off suspension components in swap and maybe ebay. If you want a more serious deep snow XLT then this is the route you should take, don't get or extend the coupled skids. I have the same thoughts for this summer, buy an XLT and extend it.

That is the direction I decided to go. I got a great deal on a RMK 144 x-lite skid on ebay. It has fox shocks and it has the SLP front shock mounting adapter that moves the mounting location forward and down (supposedly "improves the approach angle of the track for better climbing and flotation").

I was going to put that skid in the SP, and extend the x-10 in the SKS to 144...

...then I got a good deal on a RMK 136 edge suspension. :D Hardly anybody bidding on snowmobile stuff on ebay right now. So now I'm going to replace the x-10 with the x-lite (direct bolt in swap for the 136 x-10 according to JBShocks site), and I'm going to replace the x-12 with the edge suspension. Hopefully I can find some used 144 edge rails. If not I'll extend the 136 rails to 144.

ivar
05-03-2009, 01:08 PM
The 136 x-10 is not coupled, and as I have found out, the RMK 136 edge suspension (as well as the x-lite) are not coupled either.


The 136 X-10 is coupled. Maybe someone took out the coupler blocks..?

The edge rmk 136" is essentially the same as a x-lite if I remember correctly.

So now I'm going to replace the x-10 with the x-lite (direct bolt in swap for the 136 x-10 according to JBShocks site),
/QUOTE]

Where did you find that the lite's direct bolt in?

skis_n_skid
05-03-2009, 03:19 PM
The 136 X-10 is coupled. Maybe someone took out the coupler blocks..?

It's got blocks but they are pretty far apart and allow quite a bit of movement in the pivot arm. I read somewhere that it's not coupled, and when I saw how much the pivot arm can move I assumed it to be correct information. Thanks for the correction.

The edge rmk 136" is essentially the same as a x-lite if I remember correctly.

I thought they looked very similar in design. The edge has a bit more travel though is that correct?

Where did you find that the lite's direct bolt in?

Here, in the text below the picture:

http://www.jbshocks.com/x10mount136.jpg

I thought I had a 136 x-10 but just found out that it's a 133.5. My mounting locations are different than from the locations in that picture.