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Backcountry 137 to 146 conversion

14K views 19 replies 10 participants last post by  JoeyWadz  
#1 ·
I have a 2015 backcountry x with the 137x1.75 track, I'm thinking of getting rail extensions and going to a 146x2.25 or 2.5 track to give me a little more traction in the deep powder, has anyone done this? Selling and buying a new sled is not an option. Rail extensions are alot cheaper than new rails in 146 and I'm not sure how I would like a 146 t motion skid so if anyone has experience doing this please chime in
 
#4 ·
Maybe it’s just me and the way I look too much into stuff, but I think the whole rail extension thing has got to hurt your resale value. Have you thought about just dropping your gearing and going with a 2-1/4” track? It will turn into an animal then, and looks like it belongs that way.
 
#5 ·
I've thought about just doing a track upgrade but not sure if I want to spend that kind of money and keep the track the same length, if the rail extensions work I would the following year put new ice age r motion rails in 146 on it I just don't want all that cost at once. Resale value is also a factor but if I like the set up I would keep the sled alot longer. Stmike did you tell a big difference when you went to 146? What gearing did you go with?
 
#6 ·
I have done the extension thing and if it were me I would just upgrade to a 146, that skid is coupled so it won’t act like a true “long track”. I found one thing lead to another, narrow up front end so put a wider ski on and so it goes..... I had a pile into the conversion for my son that by the time we were done we could have bought a nice 600 Summit, but the time we spend together on the build was pretty awesome, so I guess in retrospect I am really happy we did it just to spend time together. If you are looking for a project there are much worse projects to do, but if you are looking for off trail capability I would buy a 146.
 
#7 ·
I've thought about just doing a track upgrade but not sure if I want to spend that kind of money and keep the track the same length, if the rail extensions work I would the following year put new ice age r motion rails in 146 on it I just don't want all that cost at once. Resale value is also a factor but if I like the set up I would keep the sled alot longer. Stmike did you tell a big difference when you went to 146? What gearing did you go with?
I used joe's clutch kit ,and 21 x 49 gears. I hear guy's saying that r motion is no good in the deep BS. Will it lift the skis like a summit ? NO.It makes a great cross over sled .Still good on trail and alot better off trail than the 1.75 x 137 . I now have a 154 summit and it is a fun sled,but some times i miss my long track BC.
 
#8 ·
Stmike, did you have to do anything other than the extensions and track? Did you need a tunnel extension or no, did 2.5 track fit without doing anything? And like you said I the r motion does not bother me as I do still like to take off down the trail from time to time and currently it does a good job but just want to make it a little better off trail and if I go out west
 
#9 ·
Shoot; I added the 2.25” FlexEdge to my FreeRide along with 21/49 gearing, and already had the DJ clutch kit. It has no issues whatsoever doing wheelies and did incredibly well in the UP and surprisingly well out in West Yellowstone this year. The snow conditions helped; sure, but it certainly exceeded my expectations.
 
#10 ·
Stmike, did you have to do anything other than the extensions and track? Did you need a tunnel extension or no, did 2.5 track fit without doing anything? And like you said I the r motion does not bother me as I do still like to take off down the trail from time to time and currently it does a good job but just want to make it a little better off trail and if I go out west
No need for tunnel extension ,just shimmed the flap with some washers .The new 2.5 fit right in ,there is a plastic guard on the front heat exchange on some sleds that has to be removed ,but none one mine.BTW when i had the skid out i drilled and taped for grease fittings on every thing that moved LOL.
 
#11 ·
I think the big reason for me to also go to 146 is if i stayed with 137 and went to a 2.3 lug i would almost guaranteed have to buy a brand new track because i wont ever find a used one of those but there are used 146 tracks around and i can get one of those for 300 to 350 and the rail extensions for 145 and be at the same price as a new 137 track. The r motion is ok with me as i still trail ride some while waiting for the snow to get deep enough in the woods but want a little more flotation for when it gets deep and climb hills a little easier.
 
#15 ·
Obviously, the decision is yours, but I'm not sure your going to see a huge difference between your backcountry with a 137" and 146" tracks (especially with a coupled skid). My regular riding group consists of 4 riders: 2 with 146" Freerides and 2 with 137" Freerides with 1.75" tracks. We ride almost all backcountry and there is very little difference between the two track lengths offtrail. Sure the 146" t-motion, uncoupled skid makes sidehilling a little easier, and is a little more "forgiving," but there's nowhere the 137's can't go that the 146's can...
 
#16 ·
I have a freeride 137 with 146 2.5 summit track, iceage rails/9" wheels and 36 front susp. No need for tunnelextension. I will say it handles like a uncoupled rear suspension..its only coupled right before I bottom rear suspension with coupleblocks on number 4. freeride r-motion are not same as renegade r-motion. But no problem to make renegade more uncoupled like the freeride. I very happy with my sled and think its a very funny sled!
 
#20 ·
I am thinking about converting my 137 backcountry to a 146 , not for power though. Just to get a bit more acceleration / traction on the trails . Thinking of an extension kit on my Rmotion with double backer picks down the center . I am roughly 235-240 lbs and really just want a bit more traction. Running a storm casmo track with 1.5 lugs down the middle and 1.25 outside .
this with an ibackshift clutch kit .. should I change gears ? Im
Looking for lightening acceleration from about 35-40 mph to 90+ I seem to spin the entire time on my 137