[Goshe]

Turn rings down raises the car up. Initial spring rate the same but gets stiffer than before as it reaches suspension stops or bottoms out because of increased spring compression. So car does get stiffer as it approaches the end of it's travel. If you're worried about coil bind do the math on the gaps compared with the shock shaft left or better yet go with a dual rate system and dial in the ride.

 

[RZR_Joe]

Initial spring rate the same but gets stiffer than before as it reaches suspension stops or bottoms out because of increased spring compression

Sorry but this is not the case, the spring rate of a liner spring does not change throughout the entire compression cycle. What you describe is a progressive spring in which the spring rate increases with the compression cycle.

Something to consider which has not been addressed is the motion ratio. If the motion ratio changes through the suspension travel it will effectively change the effective spring rate. One would need to model the suspension geometry to check for ratio change through movement. Sorry but it's not that important and this is not NASCAR 🤷‍♂️

 

[rjp2338]

Here's a little better reading material from what I consider one of the best in UTV suspension....hope this helps and best of luck. The Truth about Dual Rate Springs

 

[Goshe]

Sorry but this is not the case, the spring rate of a liner spring does not change throughout the entire compression cycle. What you describe is a progressive spring in which the spring rate increases with the compression cycle.

Something to consider which has not been addressed is the motion ratio. If the motion ratio changes through the suspension travel it will effectively change the effective spring rate. One would need to model the suspension geometry to check for ratio change through movement. Sorry but it's not that important and this is not NASCAR 🤷‍♂️

For every inch you compress the spring you increase the resistance force. The more you compress the spring the more resistance force is applied. It's at the end of the travel you notice the spring change more than the beginning.

 

[BondoMan]

For every inch you compress the spring you increase the resistance force. The more you compress the spring the more resistance force is applied. It's at the end of the travel you notice the spring change more than the beginning.

Adding preload doesn’t compress the spring, it extends the shock and increases ride height.
Linear springs do not change rate anywhere in their compression. They only change the resistive force.

 

[Goshe]

Adding preload doesn’t compress the spring, it extends the shock and increases ride height.
Linear springs do not change rate anywhere in their compression. They only change the resistive force.

Think about it it raises the vehicle but you're turning the rings down so at the end of compression there is more spring compression therefore more resistance.

 

[BondoMan]

Think about it it raises the vehicle but you're turning the rings down so at the end of compression there is more spring compression therefore more resistance.

Yes at full compression there is more spring force, but the rate is still the same.

 

[RZR_Joe]

For every inch you compress the spring you increase the resistance force. The more you compress the spring the more resistance force is applied. It's at the end of the travel you notice the spring change more than the beginning.

That's not how a linear spring works. I think you are confusing compression force with spring rate. Spring rate does not change on a linear spring no matter how far it's compressed.

Spring Rate (performancetrends.com)

What are linear springs and how do they work? (motioncontroltips.com)

 

[Dacaur]

Think about it it raises the vehicle but you're turning the rings down so at the end of compression there is more spring compression therefore more resistance.

Let's think this through. After you add preload, yes, at the end of compression, assuming you don't have so much preload that you get coil bind, you will get to a point where with less preload the shock would have been completely compressed.
Adding preload exposed x inches of extra shock shaft, so you have x inches of extra compression before the shock is completely compressed, so the full force exerted by the springs "at the end of travel" will be more than it was before, but not more than hitting the internal stop in the shock...
Obviously hitting the end of shock travel will give a worse ride than whatever extra travel you get by adding preload.

 

[Reverend_FNG]

static vs dynamic travel within a system

 

[SoonerRC]

@Chopstix Kid Is everything factory? If so, I would start with the preload adjustment in your owners manual. If I looked at the correct manual (2018 RZR XP4 Turbo?), it's on page 151. It tells you how to adjust the preload to "keep the shock in the optimal zone and maintain ground clearance" for additional weight.

 

[Reverend_FNG]

@Chopstix Kid Is everything factory? If so, I would start with the preload adjustment in your owners manual. If I looked at the correct manual (2018 RZR XP4 Turbo?), it's on page 151. It tells you how to adjust the preload to "keep the shock in the optimal zone and maintain ground clearance" for additional weight.

Good post.

The more I go down the suspension rabbit hole, the more there is misapplication of nomenclature with a stock set up.

 

[SoonerRC]

The more I go down the suspension rabbit hole, the more there is misapplication of nomenclature with a stock set up.

No doubt. I took off down that same rabbit hole before I thought twice about it. LOL

 

[Reverend_FNG]

No doubt. I took off down that same rabbit hole before I thought twice about it. LOL

For a stock set up:
The tender is actually a helper to maintain the gap of the main spring at full shock extension. It is a single spring rate system.

Yes, the shock provides some resistance to the machine weight but will not support it without springs.

For stock. Think of the main spring as a solid entity. All you are doing is moving the "perceived" hard stops of the spring. IE shock has 18" of travel. "Solid mass of spring" is only 10". Where you place that in the system will be your ride height.

If you go the full 18" of extension and occupy that with spring, then start compressing the spring down to 6" between hard stops you get into rates. Think of a captured recoil spring in a firearm. it can only travel X distance. A firmer spring will slow the motion down.

Forgive me if I am not making sense. Jacked up on allergy and cold meds.

 

[Chopstix Kid]

@Chopstix Kid Is everything factory? If so, I would start with the preload adjustment in your owners manual. If I looked at the correct manual (2018 RZR XP4 Turbo?), it's on page 151. It tells you how to adjust the preload to "keep the shock in the optimal zone and maintain ground clearance" for additional weight.

Did that... I'm about 1" longer than the range. New springs at the end of the season if the economy doesn't collapse by then.

 

[SoonerRC]

Did that... I'm about 1" longer than the range. New springs at the end of the season if the economy doesn't collapse by then.

Oh, OK. Did I miss that somewhere? I'm sorry if I did but that's where I was headed. LOL.

 

[Chopstix Kid]

Oh, OK. Did I miss that somewhere? I'm sorry if I did but that's where I was headed. LOL.

I might not have posted back. I'm about 1/2" over factory in front but 2" over factory in the rear because of all the shit I carry. I may have to reconsider how much I carry based on how we are riding that day. Adding that extra weight of the spare and carrier really fuked things up.

 

[turboedsupe]

Just buy a set of tender springs and be done with it

 

[Goshe]

That's not how a linear spring works. I think you are confusing compression force with spring rate. Spring rate does not change on a linear spring no matter how far it's compressed.

Spring Rate (performancetrends.com)

What are linear springs and how do they work? (motioncontroltips.com)

I shouldn't have used the word rate, my bad it's force that I'm referring to and how the ride will feel stiffer.

 

[Dacaur]

I shouldn't have used the word rate, my bad it's force that I'm referring to and how the ride will feel stiffer.

It doesn't matter what you you use, you are wrong. Adding preload to get back to factory ride height does not and physically can not increase ride stiffness.