Ride height

Chopstix Kid said:

After installing my @CageWrx tire carrier and dropping on the spare, I'm sitting about 1.5" low in back. If I have my head wrapped around this correctly, I'm maxed out on height adjustment since the tender springs are fully compressed? Thanks!

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So based on the info under your pic for your machine the factory preload setting (which can be found in your owners manual) is 6.35" measured from the bottom of the shock cap to the top of your preload ring. Ideally with your machine ready to ride(meaning you, passengers, fuel and whatever cargo) you should be about 13.5" of ride height in the rear with factory sized tires. (Front should be at 14") So you can increase the preload to help raise machine closer to that 13.5" ride height. As stated the upper spring is really just a tension spring. This machine does not have a true dual spring setup. Only thing to be aware of is that Polaris recommends to not exceed more then an inch over the factory setting for preload. (So don't go more then 7.35" of preload) If you can't achieve ride height with that much preload the way to correct it would be to swap out factory springs with higher springs rates to handle the higher payload. As for the ride it should actually still feel fairly close to how it was before you added the weight. Only time it will feel "stiffer" is if you take the weight back out of it and leave the preload unchanged. Hope this helps.

Actually, he is right. Adding preload without adding any additional weight to the vehicle will increase ride height but will also ride much stiffer. Springs are rated by lbs/in. Meaning if you have say a 200# spring it would take 200lbs to compress it 1 inch. To compress that spring another inch is now going to take 400#, another inch 600#, etc. This is the whole reason why increasing preload raises your machine. You're increasing how hard "it's pushing" against the weight of your machine. This is also why owners manuals state to increase your preload when carrying higher payloads in the vehicle. The added weight in the machine is now "pushing harder" against the springs which is why you lose ride height. It is also why the manuals also state to set preload back to where it was once the added weight were to be removed. You are correct in that you can not change the spring rate itself. A 200# spring will always be that. Another thing you point out is the length of the springs after increasing preload will be the same. This is false.... if say the bottom of your preload ring (where the top of the spring pushes against) and the spring cup (where the bottom of the spring sits in) are 16" apart, then your spring is compressed to a length of 16". Now, if you adjust your preload ring another inch the 2 points are now 15" apart. So there is no way your spring is still 16" because well....math.....So, to the rider the added preload will most definately be felt as a "stiffer" ride. The only way to increase ride height without changing the "feel" is to change the shock mounting positions. Either a lower upper shock mount (typically on the frame of the machine) or raising the height of the lower shock mount (typically on the A arms or trailing arms) hence what is typicly referred to as a "lift kit".

@chopstix, does not matter if springs are linear or progressive rate. If you add preload its going to add compression tension to the spring and it's going to "feel" stiffer. In addition if it is a progressive rate spring it also means that the secondary rates of that spring are going to engage sooner making the ride feel even stiffer in a shorter amount of shock travel.

@YAMAHA, "preload" is referring to tension placed on the spring prior to the weight of the vehicle. Using my above example using a 200# spring. Say that spring uninstalled is 12" in length. You install it onto a shock and say the manufacturer states it should have .5" of preload. So in other words you compress the spring to 11.5". There is now 100# of tension on that spring before its even installed onto the machine because we have compressed it a half inch. Think of it more like "pre-tension". You are simulating a "load" placed on the spring by essentially squeezing it together using the collar and threaded shock body.

Decaur:
Mostly, yes. "Preload" has no affect on ride outside of above. Different "Spring Rate" does affect ride quality. EG: It's not "just" for ride height. Which is why so many of us use dual rate springs and etc. And of course then run a much stiffer primary. We need to slow the hit down fast once we travel through the relatively soft dual rate component.

Shame we don't have progressive in the sizes we need.

RJP:
Well, that's one take one it. I suspect most of us don't agree, but so be it.

Chop:
Joe called this correctly and simply. SHO has told you correctly as well. This gets more clear when you start building your own spring packages. I will modify SHO's statement just slightly:

"So long as the spring has not sagged to such a point it will not "spring bind" at full shock compression" then, as SHO has said, there is no practical change to ride quality ss a result of adding pre-load to go gain correct clearance etc. Well, on s standard rate shock. On any multi-rate bypass - needle etc shock it will actually ride softer by getting the shaft back up into the softer valving area or travel.

Now, as to how to do it most easily: The guy that wrote this is an idiot, but it might accidentally be of help.


Luck to you!

-d

rjp2338 said:

. Another thing you point out is the length of the springs after increasing preload will be the same. This is false.... if say the bottom of your preload ring (where the top of the spring pushes against) and the spring cup (where the bottom of the spring sits in) are 16" apart, then your spring is compressed to a length of 16". Now, if you adjust your preload ring another inch the 2 points are now 15" apart. So there is no way your spring is still 16" because well....math.....So, to the rider the added preload will most definately be felt as a "stiffer" ride. The only way to increase ride height without changing the "feel" is to change the shock mounting positions. Either a lower upper shock mount (typically on the frame of the machine) or raising the height of the lower shock mount (typically on the A arms or trailing arms) hence what is typicly referred to as a "lift kit".

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That's the thing you are wrong about. The "at rest" (vehicle weight on the suspension) spring length does not change when adding preload. If it did then yes, you would be correct it would make it ride stiffer, but it simply cannot. Preload is "pre" loading the springs, but once you actually put the weight of the vehicle on it, the amount of preload you have doesn't affect the length of the springs. I challenge you to give it a try. What you are saying makes sense in your head, because you don't really understand how it works. Measure your springs between the preload ring and opposite perch, then add some preload and measure again. Just make sure to fully settle the suspension and move the vehicle before measuring each time. The spring length remains the same, you just have more shock shaft outside the shock.
You should add preload when you add weight because the extra weight compresses the loaded spring farther, reducing ride height. You want to remove the preload when you remove the weight simply because I'd you don't you will have too much ride height, which reduces your available down travel.