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Suspension setup advice needed

PAvector

Lifetime Member
Joined
Feb 24, 2007
Messages
209
Location
Pennsylvania
Country
USA
Snowmobile
2014 Yamaha SR Viper
Currently running YamaCat dual rate ski springs with 150-zbroz front skid spring and 2014 rear torsion springs in the lowest setting. 2016 2” rear shock and all other shocks where re-valved by our recommended vendors. Front skid strap is stock and rear coupling blocks are on 1 if i can read it correctly, least amount of coupling.

Just came home from a 1200 mile saddle bag trip in Quebec and the sled handle flat and great with my 30-40lb saddle bag on the tunnel, skid only bottomed out 2-3 times a day. When the saddle bags where off the sled, the back of the skid seemed to kick back when it got even slightly rough or stutters. Can I have a both worlds of saddle bad and not with the below parts or need special valving. Thoughts?

Available for the front skid is 150-zbroz, 160 stingray, 135 lbs stock and the 80-200 cat. Also have the 2014 and 2016 torsion springs.
For the ski, I have the stock straight rate and YamaCat dual rate springs.

2014 Viper LTX
 

There is no difference in the 14 /16 torsion springs, both are 18# 80* springs. Saddle bag weight would have you adjusting the blocks maybe one turn on one side only. This bottoming out with saddle bags and bucking without makes zero sense unless you have the incorrect torsion springs. Example would be your tunnel can add 20 - 40 pounds of snow/ice weight in a day. In that case you add one turn on your coupler block (one side). What do you weigh in street clothes? I'm 210 in street clothes and changed just one torsion spring, I run a stock 18# 80* on one side and a 20# 80* on the other side. This is on both my sleds, a 16 RTX Viper and an 18 LTX Sidewinder. I don't bottom on either sled but also have premium shocks on both.
 
2014 spring is .405” and the other set I have is .393” on the square. 14 and 16 ltx have different part numbers
 
The 2014 LTX rear torsion spring where very stiff.
There was quite a discussion here when those sleds came out.
I re-bent mine to achieve a more compliant ride.
These are pictures of the before and after spring angles from 2015
1675558191445.jpeg

1675558285392.jpeg
 
I learned something today....sorry PAvector. Here is what I'm going off, in our group there 2 14 Vipers one an RTX and the other an LTX and 2 16 Vipers one a RTX and the other an LTX. The kid that rides the 14 LTX is 175# in street clothes and he's never complained once about it bucking or bottoming. The 3 other machines all use the same torsion springs, can't believe I never noticed those torsion springs on the 14 LTX are that much different. We had to do major work on that skid this past off season, he broke the upper cross bar which basically destroyed the suspension, rails, W arms, center shock and more. Stain that's taking a lot of preload out of that spring, how did it ride afterwards?
 
I learned something today....sorry PAvector. Here is what I'm going off, in our group there 2 14 Vipers one an RTX and the other an LTX and 2 16 Vipers one a RTX and the other an LTX. The kid that rides the 14 LTX is 175# in street clothes and he's never complained once about it bucking or bottoming. The 3 other machines all use the same torsion springs, can't believe I never noticed those torsion springs on the 14 LTX are that much different. We had to do major work on that skid this past off season, he broke the upper cross bar which basically destroyed the suspension, rails, W arms, center shock and more. Stain that's taking a lot of preload out of that spring, how did it ride afterwards?
After a revalve from Hygear on all 4 shocks, dual rate springs up front and in the center shock, like a couch. It sucked up all the trail chatter like it wasn't even there. Those front springs were very stiff also.
That sled went from being the stiffest sled to the best riding sled I owned after those changes.
It was Hygear who told me to bend that spring from 90degrees to @110degrees. They where doing the same thing at the time. They did not have any softer springs at the time.
I need to get my Sidewinder to ride like that Viper did.....
 
Now I understand the bucking as this sled has no sit in with those 14 torsion springs and is riding at the top of the travel. Lets try and get to why it is bottoming with just the saddle bags attached. Even with that weight being further back from center it can increase it's load overall on total weight. Still not enough though to have it bottom I wouldn't think. PAvector what shocks are in the rear of this skid?
 
Using the revalved 2016 2” Taiwan shock. Don’t mind the light bottoming 2-3 times a day. At least I know it’s using all the travel.

Based on STAIN comments, I might look at bending the springs to reduce the preload, then I can put the preload blocks to 2 or 3 when saddlebaging. But maybe going to the 16 springs would accomplish the same?
 
Last edited:
I would get lighter springs. If Yamaha doesn't have them, then Cat might.

 


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