I have asked this question before and got a couple of replies but not what I was looking for. I am trying to find a good idea for a rear suspension for a Fl250. I am also installing a 440cc snowmobile Engine as well. I saw one good set up for the 250 that had an independant suspension for the rear tires. It was called the Challenger and a link to the pic is on this home page, link is called Challenger project. I know they quit makeing that set up but does anyone have any ideas where I might be able to find any parts for a set up like that?

I am currently working on suspending an FL250, but progress will be slow and as I have time. I have the basics figured out now. Its just a matter of getting the details on a few pieces worked out before proceeding any further. You can see my current progress at http://www.g2-innovations.com/

Here's mine: http://members.shaw.ca/Odyaddict/welcome.htm

How about some details on how you did your rear axles

First I flipped the chaincase center mounted it, and put the driven clutch on backwards. The 250s chaincase gears are straight cut so it runs just as good backwards as forwards. I took an old broken 250 stock axle, cut the parking brake side off and inserted it backwards into the chaincase so the parking brake splines are now driving the shortened axle. This leaves you with about a 10 inch axle with a wheel hub spline on one side and a roughly 1 inch shaft on the other. Next I took a stock wheel hub and turned it round in a lathe to make it a removable flange for bolting the right driveshaft onto. For the left, i made a same diameter flange and welded it onto the 1 inch end of the axle for the left flange. This makes it all removable for servicing. The driveshafts are 2 front driveshafts from a suzuki samurai with slip yokes. They are shortened to about 12 inches. for the outboard u joint yokes i used some from a tracker as they are forged and use the same u joint. To drive the wheel hubs i cut the ends off a stock 250 axle and welded the stubs into the forged tracker ends. Then i made some bearing carriers and trailing arms ect. The flipped driven clutch requires an extra bearing on the out side to prevent vibration at high speed. And i added a bearing to the rhs of the shortened axle to stabilize it. It has been a good design and has worked flawless for over 4 years now. Benefits are that the axles u joints and gearcase don't take any side loading and the chaincase and axle are more solidly mounted. I havent had any sort of failure with the chaincase whatsoever since reinforcing it with the extra bearing ect. This setup allows 10 inches of wheel travel and works well. I used rear pilot shocks and have perloaded the springs with a 2 inch spacer. They have 15w shock oil in them with 200 psi nitrogen. Here is a scan of the original plans i gave the machinist. They were fine tuned along the way but the basic idea is there.

Pic of axles

1 more original rough idea

I am not quit understanding the flipped chain case. If you turn the chain case around isn't going to make it run backwards instead? Or did you have to do something to the inside of the chain case?

why would it run backwards? input is input no matter what direction you have it in

When you flip the clutch also it drives the case in the correct direction. Trust me it works heh. It is both a chain case and a gear case, chain drive with a gear reduction. bty, my bro n law has the same thing with a 340 twin sled motor (( Internal Combustion Engine ? )) in it. the case handles wheeleing dry pavement launches no problem.

Thanks I get it now. I guess I was having a brain fart and thinking about it to hard. Do you have any other pics or drawings etc? So far everything you have given is real helpfull. What did you use for the actuall trailing arm hub? Do you have any pics of the complete set up with the tires off? I am just trying to get as much information as I can. Thanks

If it stops raining im taking it out tomorrow and will get some pics.

I’m not a big fan of the U-joints and slip joint arrangement (too much friction) but it seams to work. Your 250 looks clean with all the mods you have done, big improvement from the picture of it in the back of the pickup after the roll. Great job.

You have any sketches of the frame mods? How about a description of that too.

When i started the project i wanted to use cv joints but funds dictated the u joint arrangement and i wanted to keep it relativly simple. It has served me well. One day i might convert to cv shafts. I don't have any frame sketches. I printed out some pilot and 350 pics and pretty much went at it with a tube bender and mig and from there. The frame and cage took less than a week to build, it was all the little things that took time. The frame and cage are scratch built from sticks of .083 and .065 wall 1-1/4in tubing.

Didn't you go by the name oddy-addict before??? Anyway I am working on a similar design but using cv joints instead of the u-joints. Right now I am looking for a couple used/bent 250 axles to help me along the way. With the cutting on the axle have you found and need to get it re heat treated or have you just run it the way it is.

I am trying to do a step by step "how-to" guide of a project similar to yours so others out there can try the same thing.

I just cut the axle and had it welded by a GOOD welder/fabricator. He didnt do any heat treating other than the stick welding heh. I kinda like Sweet_Oddy better heh. Gone from addiction to more like tunnel vision. Cv joints are an awesome way to go once you figure it out. One reason i went with slip yoke shafts was so i didnt really have to consider axle plunge with the trailing arm design, and i have zero camber change as the suspension moves through its travel. actually i am still using the original u joints that came with the shafts hmm. Well i gotta go do some wrenching it rained all day yesterday and should make for some good mudding today. Im testing the 300ex hydraulic rear brakes i put on

Any updates?