Viper LTX Rear Suspension Sag Issue

[WisconsinViper]

I just ran my 2015 Viper LTX 140 miles for the first time this season, all was well. A few days later I went to take my sled off my tilt bed trailer. When the sled came off the trailer and hit the ground the rear suspension sagged. It compressed about half ways and stayed there. Now the sled was off the trailer and on flat ground. Without getting on the sled the suspension was still about halfway compressed. With very light weight (about 10 pounds), the rear suspension compressed all the way. If I lifted on the tunnel I could get the shocks to fully expand, but it barely holds and if I get on the sled, it would compress back down to the track. The temperature outside was around 30 degrees (warmer in the day and cooler in the nights). My first thought was that maybe some water got in the shocks and froze/thawed multiple times. I pulled the sled into the garage and heated it up to about 55 degrees. After a few hours I checked the suspension and it was better, but still compressing easier than normal. After a few days I decided to put the sled back on the trailer to take it to my local dealer. Within an hour of being back in the cold (30 ish degrees), now the suspension is back to normal. It takes a lot more weight to get the tunnel to move and it seems everything is fine. I have checked all torsion springs as well as the coil on the center shock and they are all in good shape, not cracks or breaks. I also checked all the plastic pretension adjusters and they are all in good shape as well. I have about 6,000 miles on what appears to be all original equipment (I got the sled with 4500 miles on it last year). Has anyone seen this before or have any recommendations?

 

[murdered141]

I just ran my 2015 Viper LTX 140 miles for the first time this season, all was well. A few days later I went to take my sled off my tilt bed trailer. When the sled came off the trailer and hit the ground the rear suspension sagged. It compressed about half ways and stayed there. Now the sled was off the trailer and on flat ground. Without getting on the sled the suspension was still about halfway compressed. With very light weight (about 10 pounds), the rear suspension compressed all the way. If I lifted on the tunnel I could get the shocks to fully expand, but it barely holds and if I get on the sled, it would compress back down to the track. The temperature outside was around 30 degrees (warmer in the day and cooler in the nights). My first thought was that maybe some water got in the shocks and froze/thawed multiple times. I pulled the sled into the garage and heated it up to about 55 degrees. After a few hours I checked the suspension and it was better, but still compressing easier than normal. After a few days I decided to put the sled back on the trailer to take it to my local dealer. Within an hour of being back in the cold (30 ish degrees), now the suspension is back to normal. It takes a lot more weight to get the tunnel to move and it seems everything is fine. I have checked all torsion springs as well as the coil on the center shock and they are all in good shape, not cracks or breaks. I also checked all the plastic pretension adjusters and they are all in good shape as well. I have about 6,000 miles on what appears to be all original equipment (I got the sled with 4500 miles on it last year). Has anyone seen this before or have any recommendations?

First of all you really should mention which shock's you have or sled package dx, se or le, which will give most of us a good idea which shock's you have, from the things you describe I'm pretty sure you have the fox floats, changing air temp and density make the air shock's act that way, I would have my fox float 3 work good all day, put it away in the trailer overnight and next morning my sled would be slammed to the ground, had to raise the rear bumper a few times to cycle the suspension and it would spring back to life, I put in a coil over and problem solved, rides better too.

 

[WisconsinViper]

Sorry for leaving some info out. I have an LTX SE, so I do not have the fox floats. The center shock is a coil over, but the rear shock is not. I am not sure of the specific shock, but the rear shock does have warning sticker on it that warns that is is it is filled with nitrogen under high pressure.

 

[STAIN]

Sounds like you are due for a shock service. Contact Cannondale here on the forum.

 

[cannondale27]

Yes I bet there is moisture in your shocks. Causes stickiness and can eventually ruin shock if enough accumulates. Revalve on the 14/15's is highly recommended also.

 

[WisconsinViper]

Just took my center shock and rear shock to Cannondale tonight for a refresh. Luckily I only live an hour away from him and was able to get taken care of quickly during the riding season. He also added a new spring to the center shock as it appeared mine was wearing out. He was right, water in both shocks. When putting everything back together I noticed that my right torsion spring might be wearing out as it was much easier to take off/put on than the left side torsion spring. This might be another reason why the tunnel is sagging on a level surface. Since both torsion springs were on the lowest setting, I bumped up the preload on the right side to add some more tension so now they are more even. I will be testing everything out tomorrow and will let you know how it goes. Cannondale gave me a huge tip in cutting off the top of the torsion spring loop holders. This way you do not have to take the bolt out to release the tension on these springs, you can just lift the springs off the holders. When the plastic torsion spring lop holders were off the skid I used an oscillating saw to quickly take the tops off. I highly recommend doing this as it will make your life much easier.

Shout out to Cannondale. If you need any shock service, do not hesitate to send your shocks to him. Lots of experience and passion for the sport and will treat you better than any dealer. My local dealer quoted $350 total to refresh my center and rear shock if I brought them in. Cannondale did them for $30 each.

 

[cannondale27]

Just took my center shock and rear shock to Cannondale tonight for a refresh. Luckily I only live an hour away from him and was able to get taken care of quickly during the riding season. He also added a new spring to the center shock as it appeared mine was wearing out. He was right, water in both shocks. When putting everything back together I noticed that my right torsion spring might be wearing out as it was much easier to take off/put on than the left side torsion spring. This might be another reason why the tunnel is sagging on a level surface. Since both torsion springs were on the lowest setting, I bumped up the preload on the right side to add some more tension so now they are more even. I will be testing everything out tomorrow and will let you know how it goes. Cannondale gave me a huge tip in cutting off the top of the torsion spring loop holders. This way you do not have to take the bolt out to release the tension on these springs, you can just lift the springs off the holders. When the plastic torsion spring lop holders were off the skid I used an oscillating saw to quickly take the tops off. I highly recommend doing this as it will make your life much easier.

Shout out to Cannondale. If you need any shock service, do not hesitate to send your shocks to him. Lots of experience and passion for the sport and will treat you better than any dealer. My local dealer quoted $350 total to refresh my center and rear shock if I brought them in. Cannondale did them for $30 each.

Now we just have to get you too a group ride! Thank You!

 

[Kkurz]

I wish I lived that close to Cannondale, I have an amazing shock guy closer to me but he wont do them for $30...