shock preload

super1c

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easy ?, more preload means harder, less means softer. My manual uses harder and softer, betheviper uses more and less. want to make sure i got my terms right. I know stupid ? but just want to make sure. Learning something new every day!!!!
 

super1c said:
easy ?, more preload means harder, less means softer. My manual uses harder and softer, betheviper uses more and less. want to make sure i got my terms right. I know stupid ? but just want to make sure. Learning something new every day!!!!

more=harder less=softer i believe this is true
 
s fortuna said:
More = Higher Less = Lower . It Dose Not Change The Spring Rate . It Changes The Ride Height


Ok now im confused. Lets do it this way, What does shortening/lengthing the spring length ( preload ) do??

Manual shows shorter the spring=harder preload
longer the spring = softer preload

How does this aply to bethevipers suspension write up when he talks about makeing the preload higher/lower.
 
Srings have a "rate" which is simply the amount of force they generate per inch they are compressed. For instance a 150lbs spring when compressed one inch will push back on what ever is compressing it with 150lbs of force (resistive force). If you compressed that same spring three inches it would be pushing back with 450lbs of force. If you put a 600lbs weight on the spring it would compress (600lbs/ (150lbs/inch)) = 4inches

Preload is the distance the spring is compressed and the resultant resistive force.

How does this relate to your sled and the terms that have been used by others?
More preload or higher preload means you are compressing the spring a greater distance and increasing the resistive force of the spring. This in turn causes a rougher ride and raises the ride-height of your sled.

Less preload or lower preload means you are reducing the distance the spring is compressed and decreasing the resistive force of the sprind. This in turn causes a smoother ride and lowers the ride-height of your sled.

Hope this helps clear things up.
Mills
 
Last edited:
super1c said:
Ok now im confused. Lets do it this way, What does shortening/lengthing the spring length ( preload ) do??

Manual shows shorter the spring=harder preload
longer the spring = softer preload

How does this aply to bethevipers suspension write up when he talks about makeing the preload higher/lower.
Don't worry about the manual. If you tighten the preload adjuster it makes the spring a little stiffer, the spring a little shorter (as its now being compressed slightly) and raises the ride hight of the machine.

To do betheviper setup you need to loosen the preload adjuster nut to the soft position which on a Viper is 118.5 mm from the bottom of the spring to the middle of the lower shock bolt. Now I tried this on my Viper this year and at 118.5mm and the front of the sled off the ground there was zero pressure on the springs and there would flop around. You can't do that so make sure you set them so there is at least a small amount of pressure on the spring. Then it will ride nice and the springs don't get hammered when you get air born.
 


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