Vintage John Deere Cyclone Snowmobile slightly modified 

Great to hear you’re going to bring an old Deere back to life! Good luck with the restoration and have fun riding it.

Thank you! Cheers!

Thanks!

I made up a template based on a 1990 Indy Trail chassis I had kicking around (same skid as the 91 Indy 500) and I placed that against the inside of my tunnel to roughly establish where the suspension mounting points should be. I am not certain if you could mount the suspension in the original mounting holes as I didn't even try. In my opinion, the suspension should be fitted to the JD chassis very similarly to the way it was in the Polaris sled it came out of in order to get the geometry of it's movement correct. It might fit in the original holes, but that doesn't mean it would work properly if mounted that way. A couple things to consider is that you don't want to mount it in such a way that the track would rub the tunnel at the top. The other real concern is that the suspension not be mounted too low in the tunnel which would then result in a nosedown attitude. It does look pretty cool to mount them that way and some people claim it makes them better in snow (which undoubtedly it would), but that can put a tremendous amount of pressure on the skis making the sled really hard to steer and very twitchy handling on hard packed surfaces. That's fine for shorter rides or if in deep snow most of the time. But on a long 6 hour ride on really winding groomed trails, it gets annoying real fast. You really want the sled to sit nice and level if at all possible. I even switched my skis from the stock monoleaf over to the multi-leaf system Deere used on the 76 models. Then I added a 4th leaf to gain a wee bit more height and reduce sag in the front suspension. That really helped. Another thing to keep in mind is that the Polaris suspension shafts and tubes are somewhat narrower than the John Deere tunnel. I positioned 4 gussett plates inside the tunnel at the mounting holes. As I recall, they were approximately 5/16" thick and effectively narrowed the shaft mounting area down to the required witdh to accomodate the Polaris suspension. I suppose I could have extended the tubes and made slightly longer shafts but this solution worked fine. I am running a standard 121"x 15" x 2.52" pitch track. I used a Trailfire hexagonal driveshaft and the drive sprockets came off of a 1980s era Arctic Cat (can't remember the exact year or model). I believe sprockets from the 78 X-country Liquifires also work.

I’m glad you enjoyed it!