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Long tracking a mxz 670

5723 Views 6 Replies 5 Participants Last post by  Land Crusher
Anyone ever long track a mxz 670? I want to do a little hill climbing but refuse to give up my MXZ. I hear the rail extentions will break off if you are hard on them. I was thinking about a 141 or 144 but I`m not sure what rails to look for.
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I long tracked my SC-10 with a rail extention kit. When I got it, it was a pretty cheezy set up! No rail underneath for the hi-fax to extend and just 3 little 10mm bolts to hold it in place along with the aluminum machined out to fit in the oblong hole where the back axle used to be.
I decided this was"nt going to do so I made a trip to the junk yard for an old rail to cut out 2-7.5 inch pieces and add to the bottom along with some 1/4x1" aluminum and a little welding.

It looks pretty trick but takes alot of fabing to do a good job of it. If you dont have the ability you should either buy the rails from the dealer or get on the web and look for a touring suspention. Dont get a summit suspention because they dont have ACM arm and all it will do is uncontrolable wheelies!
You also need a tunnel extention kit. I picked all this up from out of Canada [there under a link on this forum]for $165.00 U.S.
I wanted to do my original SC-10 so I could still use my AD Bolvin couplers and comet rebuildable shock. I have beat the crap out of this set up with 0 problems!
Add a 1 1/2 paddle to this and HOLD ON!!
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I also made a 96 mxz 670 into a long track, and I tell you a summit of the same vintage does not even compare. I started out with a 136-2" for a year and the next year I tore it all appart and built my own complete tunnel out of .080 aluminum, put it all back together but this time with a 141-2" and does it climb. I just finally sold It to my buddy last season and he loves it. If you need any info just let me know!

About the extensions I used them and had no problems I got them to go from a 121 to a 136 and when I went to the 141" I just moved my whole suspention back 2.5" which is good because if you ever ad extra vert drivers you have to move it back anyway.
Did you roll the chaincase on yours? Also, Where did you get your 136 extensions, and how do you move the suspension back 2.5 inches to go with the 141 ? Sorry to sound like a rookie, but growing up in west Texas did'nt give me a lot of sled wrenching experence. But I am anxious to learn. Heck I've got three Ski-Doos and these things never break, I guess I`m still not gaining wrenching experence on snowmobiles. LOL
Thanks for the reply,Don
the rail extensions I got from specialty sled .com and yes the chain case is rolled you can buy a template from him as well and do it in your own shop and for moving the suspension back all you gotta do is from your old suspension holes measure back 2.5 inches back and redrill, the back brackets have to be moved as well but thats easy just grind off tho old rivets and redrill.   How I got the 2.5 inches is for example your suspension is set up for a 136 and you want to go to a 141..    141 minus 136 = 5 inches longer of a track, half of that is 2.5
lets say a 121 to a 136 minus 121= 15 half of that is 7.5 GET IT but you wouldn't do a 121 to a 136

hope this helps and feel free if you need more info
Trade that antique in on a 2002 Black summit 800X that will fix all you long track blues
I know where there's one with your name on it.
actualy some good advise would be to sell your sled and buy a 99 sumit x
you would spend less money doing this and the 670 sumit x will have
more power....

at least keep a open mind and check into this option...

buy the time you buy a used track and all of the rest of the parts you will
see that this is good advise
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