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new torsion spring option for RM skid

17K views 28 replies 17 participants last post by  Kurt'sEtec 
#1 ·
I have been dooing some late season testing with torsion springs on the RM skid. The common next size up from the 158-159 stock torsions was the 270-271 series. these springs for some riders have been working great, other say its too stiff OR motor is running hot in soft snow, low snow conditions. BRP didnt have the following springs I tested as an option for the RM skid but for the 154 free ride, same spring dimensions though

the 503 191 287 and 289 work VERY well. The leg of the spring heading to the rails is about 15mm shorter but thats OK, all else fits perfect. they are a great inbetween from the 158 stock 120" and 137" RM torsions and the beefy 270-271. I first rode the sled in 40* weather, soft snow, no cooling issues, no shock clicker changes and immediately noticed i got back the suppleness that was somewhat lost going from 158 to 270 series. dont get me wrong, the 270's will be just fine still for bigger guys, people who pound that sled BUT not for everyone

i also gained 1" closer to the ground of the snowflap and of course that 1" more rider sag is key in the springy RM skid

you may ask "how do the 158 stockers with your torsion spacers compare to the 287 w/o torsion spacers?" GREAT QUESTION as I tested that too! similar ride but 2 more clicks on the non QA adjuster needed to gain a similar ride as 287 w/o spacers. I havnt tested these new springs with spacers, i hope to soon.

SPECS for your brain !

158-159 stock on 120/137 skids with rMotion

*newton meter 135

*wire dia 9.14

*opening ang 80*

287-289

*NM 144

*9.525

*80

270-271

*1.66

*9.86

*80

testing all these back to back with all having the same opening angle is the best test. sometimes a NM spec looks good but the opening angle is 100* and that tends to have too much free sag. so many little things go into torsion spring choices and whats the right one. I wish I had though of this last season! I did see some similarities between the mountain skids and the RM last season but didnt put forth a good enough effort, my apologies!

the 287 spring choice is a very good one for a moderately aggressive bump rider who sits a decent amount of the time ranging in weight of 175 to 225# and needs more than what the stockers can offer but not the big jump to the 270 series

Ian
 
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#3 ·
Hey Ian,
Great post. How do these compare to the stocker for sag? Meaning I'm 210# and in previous convo's you have mentioned I should run the rear torsions on 3-4 for non QA. I understand the QA is 1 step less per setting. Meaning #3 torsion block = #2 QA. Is that correct?

On #2 I get pretty close to the 4'' drop you recommend but sometimes feels spongy/springy. If I go up to # 5 then it's firm and seems to ride better but I don't get 4'' of drop. Rear clicker is on 6 or 7.

Would these "in between" springs help me find the sweet spot between correct height and feel of the ride, plush and spongy vs firm?
 
#5 ·
That's great to hear. After a few guys were saying the 270-271's were too stiff the next option was the spacers with stock torsions. Now there is another way to go. Another off season project....once I figure out how to get the QA's off and the skid out. I did see the write up also.
 
#7 · (Edited by Moderator)
Hey Ian,
Great post. How do these compare to the stocker for sag? Meaning I'm 210# and in previous convo's you have mentioned I should run the rear torsions on 3-4 for non QA. I understand the QA is 1 step less per setting. Meaning #3 torsion block = #2 QA. Is that correct?

On #2 I get pretty close to the 4'' drop you recommend but sometimes feels spongy/springy. If I go up to # 5 then it's firm and seems to ride better but I don't get 4'' of drop. Rear clicker is on 6 or 7.

Would these "in between" springs help me find the sweet spot between correct height and feel of the ride, plush and spongy vs firm?
your formula is somewhat accurate however the shock 's integrity plays a role in sag too

4" is baseline, some need more, less and everyone "feels" their sled differently. TEST AND TUNE! TINKER!!!

these springs will provide better bottoming resistance and maintain more initial plushness than 270 series can

I'm glad to hear this because I have not been thrilled with the 270/271 springs the last half of the season for the reasons you listed.
soft spring snow for cooling, hard bumps, 270's suffer. i have done alot of miles with those and overall happy but there is always room for improvement. a 250# guy SHOULD like them, i am 185 ish

What is the rating for the 270 as far as weight? Are these off the two up models?
no true way to rate for weight vs spring spec. its moreso whats known to work for certain riders. fair educated guess for a plush ride with 270's is 250 and up#

ANYONE INTERESTED IN THIS?

I'll send you a pair of the 287-289 torsions for $50 shipped to lower 48, you test them NOW if you have rideable snow, can ship a set monday ups ground. I want someone who HAS the 270's now and looking to confirm what I feel

EMAIL ME if you want to be the test dummy, post here too please that you will do this for us! if you dont like them, ship them back after a couple rides for a full refund

just ONE person please, unless each after wants to pay 75 shipped, still a deal!

ian@monsterperf.com

thank you

ian
 
#11 ·
they are $97 pair list

i had a few late seaosn customer like the softer rid ethan the 270 series, better than the 158 series for sure. a couple guys said the 270 tracked better in deep whoops for them but overall the once i am suggesting here were a great improvement

i really wish i knew this option was available 1.5 years ago! at the time myself nor anyone else though of it, until i did some looking and digging and bought a bunch of springs for fitment in the shop
 
#12 ·
I was really unhappy with ride quality of 270s and put the new mid range springs on this summer. First had rear shock off and she sat real low. I am 260lbs. then installed shock with fresh 300 psi charge, wow what a difference!Perfect sag with qa on 1.I expect after they break in they will need to be cranked a bit and cant wait to feel the stutters or should I say not feel them.
 
#13 ·
I have been dooing some late season testing with torsion springs on the RM skid. The common next size up from the 158-159 stock torsions was the 270-271 series. these springs for some riders have been working great, other say its too stiff OR motor is running hot in soft snow, low snow conditions. BRP didnt have the following springs I tested as an option for the RM skid but for the 154 free ride, same spring dimensions though

the 503 191 287 and 289 work VERY well. The leg of the spring heading to the rails is about 15mm shorter but thats OK, all else fits perfect. they are a great inbetween from the 158 stock 120" and 137" RM torsions and the beefy 270-271. I first rode the sled in 40* weather, soft snow, no cooling issues, no shock clicker changes and immediately noticed i got back the suppleness that was somewhat lost going from 158 to 270 series. dont get me wrong, the 270's will be just fine still for bigger guys, people who pound that sled BUT not for everyone

i also gained 1" closer to the ground of the snowflap and of course that 1" more rider sag is key in the springy RM skid

you may ask "how do the 158 stockers with your torsion spacers compare to the 287 w/o torsion spacers?" GREAT QUESTION as I tested that too! similar ride but 2 more clicks on the non QA adjuster needed to gain a similar ride as 287 w/o spacers. I havnt tested these new springs with spacers, i hope to soon.

SPECS for your brain !

158-159 stock on 120/137 skids with rMotion
*newton meter 135
*wire dia 9.14
*opening ang 80*

287-289
*NM 144
*9.525
*80

270-271
*1.66
*9.86
*80

testing all these back to back with all having the same opening angle is the best test. sometimes a NM spec looks good but the opening angle is 100* and that tends to have too much free sag. so many little things go into torsion spring choices and whats the right one. I wish I had though of this last season! I did see some similarities between the mountain skids and the RM last season but didnt put forth a good enough effort, my apologies!

the 287 spring choice is a very good one for a moderately aggressive bump rider who sits a decent amount of the time ranging in weight of 175 to 225# and needs more than what the stockers can offer but not the big jump to the 270 series

Ian
I really want to try the 287/289 springs cause I double alot but I keep hearing guys having trouble with the springs pulling out of the plastic holder due to the 15mm shorter in length. Not sure what I should do. What do spacers do to the stock rmotion springs?
 
#14 ·
i havnt heard of this issue at all? I rode the spring the sled pretty good with these springs and let a 300# big freind ride it for a few hours too.

once engaged in the holder and sticking thru the retainer at the rail how can it "pop" out? the rear arm would have to travel rearward pretty far. on the bench i could see that happening, normal with any skid not bolted into the tunnel.

our torsion spacers with 158 stock torsions give a little more preload range, touch stiffer feel, smoother rebound as well
 
#15 ·
i havnt heard of this issue at all? I rode the spring the sled pretty good with these springs and let a 300# big freind ride it for a few hours too.

once engaged in the holder and sticking thru the retainer at the rail how can it "pop" out? the rear arm would have to travel rearward pretty far. on the bench i could see that happening, normal with any skid not bolted into the tunnel.

our torsion spacers with 158 stock torsions give a little more preload range, touch stiffer feel, smoother rebound as well
This is my first rmotion suspension and i want to be ready to change the springs if i am bottoming out. Its a 13 mxzx but without QA so its apparently 40% less tension so i am kinda concerned reading on here. What would a set be worth shipped to manitoba,canada? Thankyou
 
#16 · (Edited by Moderator)
here is the 2012/13 BRP revised sc5m-tmotion-rmotion spring sheet from my website, a PDF. I have several PDF's there in the FAQ's section at the bottom of the page. all the below springs are on that sheet too for use in those suspensions

http://www.monsterperf.com/2013_skidoo_spring_chart.pdf

the picture belows shows 3 springs lined up symetrically above (not seen in pic). 270 series on left, stock 158 series in center and 287 series on right.

note the lower red line, upper red line and paint worn off from middle (wash) on the 158 spring running thru the retainer for a few hundred miles. the lower red line shows the end of the wash, hardly any to be seen. the un-washed area closer to the red lower line is what sticks out the front side of the torsion retainer at the rails and whats within the retainer at full UP of rear bumper. most all of the travel is in the heavily washed area with the upper red line being near full bottom of rear arm, lower red line being full rear bumper UP, locked, cant go any farther.
 

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#19 ·
Ian,

Thanks for the service bulletin. I have a question. I just bought a '14 GSX SE 1200 (air ride/rmotion) and see the rear springs are 503 193 636 1.13 90. What are these in relation to the 158/270/287?
 
#21 · (Edited by Moderator)
2013 Renegade here, so I'm supposed to have the 158/159's. I'm about 235 in my bday suit, and I also got the 1+1 seat for when the wifey or kids want to ride too.......safe assumption to just switch to the 270/271? Thing is, with springs on lowest setting now I dont get the 2" static sag.....guess I will have to look at mine closely and see what they are stamped.
 
#22 ·
2013 Renegade here, so I'm supposed to have the 158/159's. I'm about 235 in my bday suit, and I also got the 1+1 seat for when the wifey or kids want to ride too.......safe assumption to just switch to the 270/271? Thing is, with springs on lowest setting now I dont get the 2" static sag.....guess I will have to look at mine closely and see what they are stamped.
 
#23 ·
Some more info for everyone on this subject. I always run spacers in all my springs whenever possible. The stock torsions on my 12 and 13 XRS were just enough for me by my self QA skid spacers (165)lbs with gear. When my wife would ride along (145) with gear it was too soft. The 289 springs were the next stiffer option. I knew the 270 would be way too much for my weight. The issue with the 289 springs is the coil is huge. U must use a custom spacer to take up the gap around the arm. If u don't all you'll gain is higher rate without the ability to set more ride height. I run monster revalved shocks with Ian's front spring kit. The centre tender was increased as well. The rear QA is set on 2.5 for myself and maxed with the wife on board. Hope this helps everyone thinking about changing springs.
 
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