In case you haven't seen it,
HERE is my 136" story.
1. Considered 8" wheels, and asked my dealer who has been very successful in racing, and had them in his shop for sale, and he said there are several other things to spend your money on for a sled that will give you a much better bang-for-your-dollar ratio. I passed. But I guess if you found everything you needed from an individual at great prices, they may be worth it.
2. There are others. I just searched two weeks ago as I am longtracking my second sled, a 2001 Tcat. I found about 2 or 3 that looked decent enough, but just didn't prove to be any better in my eyes than Cat's extension. I don't like Track USA's because you have to cut part of the 121" extension off. True, you'll probably never use that part again, but Cat's part overlaps the original tunnel for about 6" which does add to the rigidity of the tunnel when finished. I ended up lucking out and found a used Cat extension. One thing that angered me while doing mine this month is that Cat has raised the price of their extension by $100, to $189. When I did my ZR 3 or 4 years ago, it was $85.95. I guess it's no coincidence that most of the mountain shops that make theirs are charging about $195...I think Cat saw their pricing and didn't want to leave any money on the table. Search "arcitc cat snowmobile tunnel extension" in google and see what you come up with. Van Amburg offers a nice product, and even Dennis Kirk has SLP extensions in their catalog that look pretty nice.
3. Any track of mentioned size should work...don't go taller than 1.25. I will be using another Ripsaw for my second time around. It has been an awesome track for mostly trail riding and about 10% playing in the powder.
4. I never changed my gearing, I think that's a myth that can be busted. Like mentioned before, I also had twin pipes and clutching on my ZR 800, so I wasn't lacking in the power dpt to start with. I will not be changing the gearing on my Tcat either.
5. My first time around my dealer was able to get me a used 136" skid from Cat, and I did exactly what you suggested. Sold the redone 121" skid and recouped all my $$$ for the cost of the 136. This time I was lucky and found a pair of used rails...I didn't want to mess with swapping out the skid arms and selling the other skid again. I know some of the new rail extensions are pretty sweet, but I just like the idea of solid rails...I just don't see how any extensions can be more solid than a one-piece rail.
6. I did not extend my coolers and never had an overheating issue in 3500 miles.
Some guys will say to use steel rivets for strength, but alluminum will do just fine. That tunnel extension is just a "cover", and doesn't really have any major continuous stress on it. The other important factor is the alluminum rivets will never rust....look at some other parts in the suspension, like the mounting plate for the rear arm, it usually starts to rust over time. For the bulkhead and other heavily stressed areas, steel is needed.
Don't forget to swap out your rear springs for new mountain cat springs. This was my biggest fault the first time around. My sled bottomed easily after converting to 136". So I ordered the next stiffest ZR springs, and they were a little better, but still not as good as they should be. This time I asked my dealer about this, the same guy as mentioned in #1, and he was quick to point out that 136 springs are stiffer than the 121 springs, for obvious reasons....made sense after he mentioned it, wish I would have asked him a couple seasons ago, lol. So I ordered Tcat Mountain Cat springs this time around.
You will have to move your rear arm mounting plate back in the tunnel. Try to mount that arm in a hole above the floorboard, and not in the hole that is below it. Mounting in that lower hole seems to make it easier for the bolts to "egg" that hole. Mounting in one of the upper holes and using the tunnel for extra reinforcement makes a difference. Make sure you only move that rear mounting hole back the same distance that the rear arm moves back in the longer skid. Take measurements before disassembling, it will help later.
It's late and that's all my brain can spew. Feel free to contact me at any time with a question and I'll try to help.
My dealer is Stan at
Triple E Sales. Brent can also help. I ordered all my new parts from them last time. They are great guys.
<div class='quotetop'>QUOTE (cat4ever @ Dec 27 2006, 10:09 PM)
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I'm gathering information on long tracking ZR's. I've alerady read one thread that had alot of useful info in it but I have some more questions.
1. Are 8 inch idler wheels worth it? I read that you need a different idler axle to use 8 inchers. Is this true? If so, who makes 'em.
2. The only manufacturer I know of that makes tunnel and rail extensions is Tracks Usa. Are there any other people who make these.
3. I decided to use a 1.25 track and am pretty sure that it would be good enough for trails and off- trail. Will any 15 by 136 by 1.25 track from any manufacturer or take off from any brand work?
4. I read in another thread that you should change gearing to 19/40. Is this correct?
5. Instead of buying the rail extensions, why couldn't you just buy a used 136'' skid from a Powder special? To me that would be the more economicial way because you could sell your stock skid to buy the 136''.
6. Is there anything else I should know or should do that I've missed?
This will be my summer project and I'm just starting to get some information on it.
Thanks a million :beer_cheers:[/b]