Snowmobile Fanatics banner

1 - 9 of 9 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter · #1 ·
Ok, I put a 98 xc 700 libery twin into my 97 Ultra X12 (formerly triple).

Overall, I had to do a little fabing, but it really wasnt too bad. I used the 700's mounting plate, the engine is now in, lined up to spec's and sitting in without any issues. air box fits and 700 gears are in w/o any issues.

Then came one of those "things that make you go Hummmmm" momments. The exhaust silencer fit in after a few minor mods, but.........the expansion chamber is about 2.5 inches too thick at the upper shock mounts on the right belly pan. This size issue will not allow the hood to set down correctly.

Now I have had several thoughts to correct this so I thought I would throw them out there for any suggestions or thoughts from the gallery that I may not have thought of.........(Cutting the hood is not an option, thats like admitting defeat!)several hundred minds are better than one!

So, I am thinking I could:

1. Use the the original ultra triple expansion chamber and silencer and simply have the flange at the manifold expanded to fit 700's mainfold. this pipe is much smaller and I would think it would create a performance issue.

2. Use the 700's expansion chamber, but use a plasma gutter to peel it open at the are of the shock mount, shink it down 2.5 in and reweld it closed. While this might effect performance some what, I am thinking it may not be as bad as #1.

3. Look for a used tunner pipe that hopefully may be a little smaller. This could be a little expensive and somewhat easy fix

4. Have custome pipe made. This could be way to expensive and too easy.


Overall I would not suggest this mock up to anyone, but I had the parts on hand and was looking for a project to challege me.
 

·
Registered
Joined
·
2,422 Posts
You would probably have to cut it down more that 2.5 inches to make sure it doesn't melt your hood but that's what I would do.
 

·
Registered
Joined
·
4,299 Posts
DO NOT MODIFY THE VOLUME OF THE PIPE!



The shape and volume of the pipe are what builds the back pressure needed to properly run your 2-stroke engine. If you alter that volume you will probably burn up your engine. What you can do is cut the pipe and rotate sections of it to refit it to your chassis. And you can NOT use the pipe from your old triple, pipes are engine specific.

For example, look at how the pipes were cut and fitted in this picture.

 

·
Registered
Joined
·
1,179 Posts
the hoods on a 98 xc are different, the pipe vent is cut out more, I can take a pic of mine and show you. I also have all of the stock mounting hardware and brackets if you are interested.
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #5 ·
I was looking at your fitted pipes, I am very intriged! but I am woundering if it would cause an air flow problem and then a over-heating issues? I am going to take a look and see what I can do...I'll get back to you on what direction I am going.
 

·
Registered
Joined
·
8,842 Posts
these are the first set of pipes i built, they took a lot of time and i did make a few mistakes.

the only thing that would cause to much heat in the pipe is to small of a stinger pipe coming out. drag racers use a much smaller stinger pipe on some engines because it helps get the pipe hot and keep it hot. the sled only runs for 4-5 seconds so its not an issue. a speed running sled usually used a much larger stinger pipe to let heat and air out of the pipe and let the motor breath. one speed runner took his sled to a shop and they built him a set of pipes that when they did a quick pull on the dyno it made a lot more hp. but on the ice the thing shot out of the hole and to 600' better then they ever have. then at 600 feet the engine and pipe were just heat soaked and fell on its face. do like power said and fit the pipe. you can change the radious coming off the engine to get the center of the pipe behind the shock tower, the hood is going up so you only need to move the pipe back a couple inch's to get your clearance. slide the pipe around and close the hood to see where you need to have it at.
20109247142346_1069.jpg
 

Attachments

·
Registered
Joined
·
4,299 Posts
Jeb293 said:
I was looking at your fitted pipes, I am very intriged! but I am woundering if it would cause an air flow problem and then a over-heating issues? I am going to take a look and see what I can do...I'll get back to you on what direction I am going.
Your engine is liquid cooled, you wont have an overheating problem of you engine. Just keep plastic parts away from the pipe.

The problem you're running in to is that the X-12 suspension has much larger shock towers and was not designed to fit a twin engine in to it. You may have to modify the hood to get it to work.
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #8 ·
Thanks folks, All of your advise has been absolutly invaluable!!!!! I am going to take it and see what I can work into this project, I will let you know the outcome.
 

·
Registered
Joined
·
8,842 Posts
its a single pipe, you should have zero problem making it fit in there.
 
1 - 9 of 9 Posts
Top