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"Big Boy" Torsion Springs on IQ: Inputs??

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raptobob

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With a .375 spring is it stiffer with the 47 degree angle vs the 77 degree angle? 205 without gear so not sure if the "big boy" setup will be a little too stiff.
 

MORSNO

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With a .375 spring is it stiffer with the 47 degree angle vs the 77 degree angle? 205 without gear so not sure if the "big boy" setup will be a little too stiff.

The 47 degree has more preload. I've had both .375/77 and .375/47 on my sled, the 47 degree worked out much better. The 77's sacked out sooner and had to be set to the stiffest pre-load the first season. The 47's can be set to the soft or medium pre-load giving a much smoother ride throughout the suspension travel.

Here is a great post from Curt at FTX Motorsports.

You should also consider the 7042079/7042080 torsion set. They use a tighter spring leg angle which gives you a little more preload at the top of the skids travel.This helps a couple things...it allows you to run the spring on a softer setting and still supports you and the sled properly which extends the life of the spring. The spring will also have more effect at the beginning of travel which helps eliminate the dead spot all these skids have-this unsprung/undampened area of travel is a big reason why the IQ was a bit on the wild side with weight transfer-to much scissor collapse right off the bat.
These are our go to springs for any one over 220#(which I'm one of by the way!) I have a full season on them in my turbo 163 and they are still on the soft setting-haven't had to add any more pre load since installation which indicates that they are not "sacking out".

curt
 

Z-Man

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So, I'm not one of these "fatties" yet..... Probably closer to 210 with gear on and if I can ever get my azz in the mood to get into shape a little bit I should be able to lower that considerably.

Anyway, my 9 has considerable sag in the rear, would those springs be what I need to take care of that? Already have the 225 in the front with the spring set with just minimal tension. I have the blocks cranked all the way up for the tension on the Torsion springs and after I get off the sled or it sits for a long time I can pull it up an easy 5-6".

Yup, heavier springs or go with a Timbersled or New Holz Suspension with infinitely adjustable air shocks. The T-sled is also 16 lbs lighter than the stock boat anchor suspension.
 

Sxrlar

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My 07 RMK 600 now has 7200 miles on it now, I think it is time to get new springs in the rear. :face-icon-small-sho I weigh 200, geared up probably 215, and with a full tunnel bag, we are looking at 220-225. Which springs should I get? Most of my riding is in the U.P. of Michigan, sometimes the trails to the fun spots get a wee bit bumpy, and I do like to jump, not Slednecks style jumping though LOL. Do I go with the 359-47* or the 375-47*?? Looks like I may go with the scissors relocation also.
 

MORSNO

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I'm a big supporter of the .375/47's. They are not overly stiff and give a great ride throughout your suspensions travel. I just did the scissors relocate myself this fall, can't wait to try it out this season. It's free and if you don't like it, just move it back.
 

Ski-Dont89

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I bought the .359/47 for mine this summer...im 170 lbs tho...if i were you i would prolly get the .375/47...im going to try the 5/8 scissor mod also...should be a big improvement over stock.
 

guidoxpress

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i have a set of the "big boy" springs for sale if anyone is interested...not the ones stated on here by Curt, but the actual big boy ones. used 1 season and installed a timbersled skid.

$120/shipped...there like $90 each normally.

i also used 6" upper idler wheels with this springs cause they were close to the track, and the 6" worked perfect!!

PM me if your interested in them..

and a TTT for one of the BEST stock skid mod threads out there ;)
 
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heavy d

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Nov 21, 2010
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Is there a part # for the 225lb front track spring? I read through the entire thread twice, but didn't see any mention of it. Is it a Polaris # ?

Cant' find it in the dealer fiche.

Thanks for the help guys
 
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heavy d

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Nov 21, 2010
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Just finished installing my .375x47' torsion springs and moving my scissor back 5/8 of an inch.........225lb spring should be here Tuesday !!!

It feels like a brand new sled (bouncing around in the garage, anyway)

Can't wait for the snow....


Thanks for all the help Guidoexpress....sled feels awesome now:becky::becky::becky:
 
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Amzoch

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Hey, have a questions about the springs. I have ordered 375/47 for my 2010 RMK 600 So I wonder if I will get the problem with the running wheel, and I MUST move Swing Arm 5 / 8 "back?
 

guidoxpress

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Hey, have a questions about the springs. I have ordered 375/47 for my 2010 RMK 600 So I wonder if I will get the problem with the running wheel, and I MUST move Swing Arm 5 / 8 "back?


are you referring to the upper bogie wheel and if it would rub the spring? if so, NO it will not rub the spring...the .405 torsion spring will rub, so you would have to use 6" upper bogies, but with the 375, you will be fine.

and you "dont have to" move the scissor back 5/8" if you read this thread, it states that the scissor reclation mod simply moves the rear torque arm back and removes the "dead-spot" in the suspension and provides a better transfer..

and its FREE, and its WELL worth doing...
 
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lognomore

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.359/47 Springs

.359/47 Springs. Does anyone have the part# for these? Looking to put them on a 07 Dragon. Current springs are pretty well sacked and my son goes around 170 lbs.
 

Dartos

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Take a look at post #39 in this thread by Mountainhorse and it should have what you are looking for.
 
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Rally2

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Bringing this thread back to life lots of good info. I'm putting the .375/77 springs in my 2012 Switchback Assault skid which I believe is same as the IQ skid.
 

94fordguy

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Heavier Rear Torsion Springs

I installed the .375/47* torsion springs on my 09 700 RMK 155 after my third ride on it this year and I couldn't possibly be happier. I'm a bigger guy (240 before any gear) and with the stock springs set to max preload, the sled would sag substantially with nothing more than my tunnel bags on it.... you can imagine what it would do with me hitting any jumps or even regular riding. With the .375/47* springs on there, there is just enough preload that the sled will now return to full extension when I step off, but ride quality is completely unchanged, no harsh stiff ride over the bumps, just PERFECT.... and that is on the softest preload. 200 miles on the new springs and counting.:rockon:


.375/47*

7042080-067 R/H
7042079-067 L/H
 
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MORSNO

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Bringing this thread back to life lots of good info. I'm putting the .375/77 springs in my 2012 Switchback Assault skid which I believe is same as the IQ skid.

Have you already purchased the springs? I had the .375/77* springs for the two seasons, then switched to .375/47* springs for much improvement for all the reasons posted above.
 
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Rally2

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Have you already purchased the springs? I had the .375/77* springs for the two seasons, then switched to .375/47* springs for much improvement for all the reasons posted above.

Yeah I already got the 77* for better or worse; was debating going with 47* but my reasoning was A) I'm a "light" bigboy just under 200lb B) I have the SLP adjuster blocks with a 4th position giving more preload than stock adjusters C) in principle I like to go conservative as possible on suspension spring rate and deal with bottoming via shock damping.

With the skid apart I got the stock W/E rear track shock rebuilt with 7w oil insteads of 5w to hopefully give it a bit more rebound damping to counter the the stiffer spring rate as well as more comp damping so I can run more mid-range on clicker position.

Note the photo showing larger 2.5" ID of new .375 springs versus 2" ID of stock .359 springs. IMO Polaris should sell a larger diameter plastic sleeve to take up the extra 1/2" diameter, otherwise the spring can twist on the shaft effectively taking away from spring rate. Someone mentioned using PVC pipe to achieve this but I'm not seeing the right diameters available or a way to prevent the PVC sleeve(s) from rubbing the idler wheel..

IMG_20120329_090240.jpg
 
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