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Discussion Starter · #1 ·
How does the Gen 4’s suspension work with torsion spacers installed. Does the sled sit too high, is the suspension too stiff and does effect the handling? I already have heavier springs installed but still have about 3 inches of free play, when I stop I can pull the back up about 3 inches.
 

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IF the coil part of the springs you have are much larger than the shaft it's mounted on the spring tends to tilt/twist a lot on the shaft resulting in the spring being loaded more sideways rather than in the correct direction. This will become MUCH better with spacers and the springs will start to work as intended.

If the coil bit isn't "too large" spacers wont do much difference at all, (if they fit at all)
 

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How does the Gen 4’s suspension work with torsion spacers installed. Does the sled sit too high, is the suspension too stiff and does effect the handling? I already have heavier springs installed but still have about 3 inches of free play, when I stop I can pull the back up about 3 inches.
Sounds like the lack of gas in the shock .Thank BRP for that .
 

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Sounds like the lack of gas in the shock .Thank BRP for that .
Nope, the shocks doesn't carry any weight, they just slow movement. It's the spring's job to carry weight.
Ride height is solely determined by the springs.
(yes the shock will provide some force from the gas pressure but nowhere near enough to make any noticeable difference)
 

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Nope, the shocks doesn't carry any weight, they just slow movement. It's the spring's job to carry weight.
Ride height is solely determined by the springs.
(yes the shock will provide some force from the gas pressure but nowhere near enough to make any noticeable difference)
KRM is correct! This has been debated and yes, shocks will have an effect on sag.

Bob
 

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I suggest you head to monsterperf.com and track down the link for their suspension setup guide.

If you are going to tackle set-up on your own (in which I would suggest) vs leaning on a dealer or the internet - the monster link is a great place to start understanding what all the adjustments do.

This will help you narrow down what/if you need to 'modify' beyond what is already there...

PS - I can pull up on the rear bumper after stop and get a couple of inches of 'lift' BUT I know that my spring preload / sag is set properly...
 

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KRM is correct! This has been debated and yes, shocks will have an effect on sag.

Bob
Hi Bob - not a call-out on you at all but I would like to hear a bit more about this as my (very) basic understanding about suspension does not align with what you are saying.

I was under the impression that spring weight/pre-loads were the primary player for setting sag then the shock internals (valving, gas, oil, etc) are what plays on how the shock performs.

Note - this is assuming coil (not air) suspension.
 

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High pressure gas shocks will assist in supporting the rear suspension. Standard non gas shocks will not. Try it yourself, start with known good gas shocks, rear suspension should go to full height with no rider. Remove shocks and see what happens, it will sag with out shocks. Also, try compressing a gas shock when out of sled (very hard to compress) and when released will return to full length if in good condition. I was a disbeliever also, until I proved myself wrong!

Bob
 

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There are 2 types of sag.

1.Race Sag is the sag when the rider sits on the machine
2.Static Sag is the sag of the machine itself without the rider

Both are equally important.
 

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Discussion Starter · #12 ·
Just some more information, I have had my shocks revalved and rebuilt but still get the sag after riding. Thought the spacers would take of this but maybe this is normal.
 

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High pressure gas shocks will assist in supporting the rear suspension. Standard non gas shocks will not. Try it yourself, start with known good gas shocks, rear suspension should go to full height with no rider. Remove shocks and see what happens, it will sag with out shocks. Also, try compressing a gas shock when out of sled (very hard to compress) and when released will return to full length if in good condition. I was a disbeliever also, until I proved myself wrong!

Bob
There is roughly 1 in 10 000 sledders that understands suspension so what is debated won't necessarily mirror reality..

I haven't seen a non-gas shock on a sled in maaaannnyyy years, have you? Some are none serviceable and some are possible to take apart but they are "all" pressurized. I service my own shocks and yes, a filled shock needs a little force to stay compressed, but it's primarily the spring that has that job, and getting the right spring and setting it up correctly is crucial and if you skip that bit a few kilograms of added lift from the shock won't save your bacon.

On spacers; As I said before, the spring spacers will make a noticeable difference IF the spring has a sloppy fit on the shaft! And as I said in another thread you can make your own from almost anything to test the function on your sled. The first pair I had, back in 2006 or something, I made late one night from plastic pipe with some pieces of cut open garden hose which I wedged in between two pieces of pipe. Was planning to make/buy beter ones later but they lasted two seasons on the sled and could have gone on at least as much again if I hadn't sold the sled. I have used different sets on several occasions later on to, all with very good result.

Sag doesn't necessarily mean something is wrong, most of it usually comes down to the geometry of the suspension. If, however, you are unable to set the sag per user's manual the springs might need to be changed. On an used sled new stock ones might do the trick but if the rider is a bit on the larger side, 100kg-ish and above, heavier springs is likely the way to go. Getting the right springs for the rider is one of the easiest, and most commonly overlooked, ways to improve the ride.
 

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Have a link? I am interested to hear their reasoning?
I am curious of this as well. One reason simply may be the lower pressure will not bleed out as easily
 

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I am curious of this as well. One reason simply may be the lower pressure will not bleed out as easily
Haven’t heard of this release , also interested. My guess is just another way of tailoring the XRS valving/setup towards the cushy/flat trail XRS owners.
 

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How does the Gen 4’s suspension work with torsion spacers installed. Does the sled sit too high, is the suspension too stiff and does effect the handling? I already have heavier springs installed but still have about 3 inches of free play, when I stop I can pull the back up about 3 inches.
Sorry OP - looks like we got a bit 'derailed' from your original question. Keep in mind I have NOT tried / used the spacers you are asking about but maybe we could get some additional 'real' experience answered here from someone that does.

I am guessing that you now have the correct sag (as you indicated that heavier springs were installed and you have had shocks 'rebuilt' for your spec's).

RE the 3" unweighted sag - I checked my sled & have 1.5" - 2" unweighted sag w/ +3" weighted (this falls w/in what seems to be the standard set-up spec) - I do have a new sled w/ custom shocks.

Looking at the function of those spacers (again remember I have not tried/used them) I am thinking this may help put your unweighted sag w/in spec ie 1.5" - 2" and should not change the weighted sag. My hypothesis is that it's possible the heavier springs don't sit centered on the bushings & that's causing a bit of havoc on your pre-load (especially un-weighted) spec. Overall my feeling is this is probably not a huge issues but the OCD in me would at least try those spacers to see what kind of affect they have.

PS - all this is assuming you have spent some time making sure all bolts are tight, bits n pieces are in good working order, etc...
 

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The more important question is does the spacer affect the springs' response, does it ride different, stiffer?
I ordered a set this year to try, I’m under the impression that it’s almost like going up a spring size with the spacers installed. That was noted in a few threads here if you search.
 
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