78 Cyclone Rear Suspension info please?

General topics related to John Deere Snowmobiles
Liquifire 4/6
Posts: 1035
Joined: Thu Mar 08, 2007 1:00 am
Location: Roblin, MB

Re: 78 Cyclone Rear Suspension info please?

Post by Liquifire 4/6 »

harleysportster wrote:That is my version of a 78 cross country clone using a 1980 skid and an Arctic Cat all rubber track.
That is sweet. What is the length of the Cat track? And did you have to alter the rail spacing of the Deere skid to fit the Cat track?
Peter from Roblin, Manitoba
harleysportster
Posts: 2965
Joined: Thu Jul 14, 2005 12:00 am
Real Name: Pat Scott
Location: Southeast Pa.

Re: 78 Cyclone Rear Suspension info please?

Post by harleysportster »

The cat track is a 121 inch, same as the 78 cyclone track. I did narrow the skid , 1/8 inch per side. Others have had good luck without modification.
'76 440 cyclone
'76 440 liquifire
'78 440 Cyclone
'75 JDX8 (sold to a member here)
'78 Liquifire(CrossCountry Clone)
'80 Liquifire(sold)
Liquifire 4/6
Posts: 1035
Joined: Thu Mar 08, 2007 1:00 am
Location: Roblin, MB

Re: 78 Cyclone Rear Suspension info please?

Post by Liquifire 4/6 »

harleysportster wrote:The cat track is a 121 inch, same as the 78 cyclone track. I did narrow the skid , 1/8 inch per side. Others have had good luck without modification.
Ok, so that's a standard 121" x 2.52 pitch track the same as used on many late model Cats, Polaris, Yamahas and Doos? I assume you were still able to use your original sprockets but did you need to relocate them on the driveshaft? Or did you just install a Cat driveshaft? I know.....it's alot of questions.
Peter from Roblin, Manitoba
sledhead16
Posts: 1386
Joined: Sat Dec 14, 2013 3:39 pm
Real Name: Allan Campbell
Location: Saint Peter MN

Re: 78 Cyclone Rear Suspension info please?

Post by sledhead16 »

It appears that is just how those cyclones sit. You could do a drop bracket in only the rear, an inch lower hole with the plate on the inside of the tunnel should work. But depending on how thick of plate steal you use it might cause the rear arm to sit really tight in between the plates.
1975 340/s Speed Run Sled
1975 340/s I500 #161
1980 Liquifire SN# 4995 From WA Speed Run Sled
1980 Liquifire SN# 4996 From MN
1983 Sportfire
1984 Liquifire Deep Snow Tunnel 4/6 motor
1984 Sprintfire (2)

***Duelling Deere Garage***
Liquifire 4/6
Posts: 1035
Joined: Thu Mar 08, 2007 1:00 am
Location: Roblin, MB

Re: 78 Cyclone Rear Suspension info please?

Post by Liquifire 4/6 »

sledhead16 wrote:It appears that is just how those cyclones sit. You could do a drop bracket in only the rear, an inch lower hole with the plate on the inside of the tunnel should work. But depending on how thick of plate steal you use it might cause the rear arm to sit really tight in between the plates.
If I could drop it only an inch, I'd go ahead and do it because I don't think and inch drop would be enough to do any funny things to the suspension geometry that might result in excessive track stress. The problem is that the existing hole center is only about an inch above the running board so there just isn't sufficient room to drill a hole underneath it. I'd have to make a bracket that hangs below the running board and would need to locate the new mounting hole around two inches below the existing hole. I could do that easily enough but I'm afraid of what that might cause for track stress problems. These tracks are getting a bit hard to come by and I wouldn't want to risk damaging this one. I'm no engineer by any means and maybe lowering the hole two inches would not cause any problems at all for the track, but I just don't know one way or another.

Having said that, a buddy of mine bought a 78 440 Liquifire late last season. I just saw it this morning for the first time and wish I had taken a camera with me. The previous owner dropped the rear mounting hole a good four inches with some sort of crude looking bracket he made. But that doesn't mean it will work long term because who knows how many miles the guy racked up on it after he jacked the rear end. I forgot to look to see if the front mount hole was lowered too. I'll have to go back and see it again.
Peter from Roblin, Manitoba
harleysportster
Posts: 2965
Joined: Thu Jul 14, 2005 12:00 am
Real Name: Pat Scott
Location: Southeast Pa.

Re: 78 Cyclone Rear Suspension info please?

Post by harleysportster »

You are not gaining anything other than a different look if you just raise the tail-end of the Cyclone. The suspension travel will remain the same, some where between 2 to 3 inches.
just saying...
'76 440 cyclone
'76 440 liquifire
'78 440 Cyclone
'75 JDX8 (sold to a member here)
'78 Liquifire(CrossCountry Clone)
'80 Liquifire(sold)
Liquifire 4/6
Posts: 1035
Joined: Thu Mar 08, 2007 1:00 am
Location: Roblin, MB

Re: 78 Cyclone Rear Suspension info please?

Post by Liquifire 4/6 »

I realize it wouldn't gain any suspension travel however I think it would likely improve the performance in deeper snow somewhat by getting the running boards a tad higher in relation to the track. But I really don't plan on doing a whole bunch of off trail riding with it anyways so there is likely no sense changing it.
Peter from Roblin, Manitoba
sledhead16
Posts: 1386
Joined: Sat Dec 14, 2013 3:39 pm
Real Name: Allan Campbell
Location: Saint Peter MN

Re: 78 Cyclone Rear Suspension info please?

Post by sledhead16 »

Yes clearance and look will be your only gain...if that's what your going for.
1975 340/s Speed Run Sled
1975 340/s I500 #161
1980 Liquifire SN# 4995 From WA Speed Run Sled
1980 Liquifire SN# 4996 From MN
1983 Sportfire
1984 Liquifire Deep Snow Tunnel 4/6 motor
1984 Sprintfire (2)

***Duelling Deere Garage***
Post Reply