I have an 05 900 RMK 159" and the springs seem to be sagged out. I'd like to replace them, but preferrably with a stiffer spring since I weigh about 280 lbs...(I'm sure that's way beyond what the stock spring is optimal for). Any ideas on I what I should get and where to get 'em? Are they hard to replace?
What rear torsion springs should I get?
- Thread starter FattyMatty
- Start date
Stock springs are made for some little engineering guy that weights around 170lbs. The largest made for the RMK skid is .375/47 and .375/77. Some guys have also used .405/77 from an IQ 2up sled. They may not fit exactly right and hit your rails, but it has been done for years. You can get them from any Polaris dealer.
Z-Man, I don't think a Mountain Tamer skid is what he had in mind for springs. Lets see $150 for springs or $2,500 for a whole new suspension.
Z-Man, I don't think a Mountain Tamer skid is what he had in mind for springs. Lets see $150 for springs or $2,500 for a whole new suspension.
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lol.
both the Mtn. Tamer and heavier springs are good mods, LOL...
read this thread...tells you EXACTLY what to do,
http://www.snowestonline.com/forum/showthread.php?t=165462
also...since your back there...do the FTX rear torque arm mod...drill 5/8" back from center of the old hole to center of the new hole.... well worth it.
both the Mtn. Tamer and heavier springs are good mods, LOL...
read this thread...tells you EXACTLY what to do,
http://www.snowestonline.com/forum/showthread.php?t=165462
also...since your back there...do the FTX rear torque arm mod...drill 5/8" back from center of the old hole to center of the new hole.... well worth it.
Go with the 405/77. I did and i'm 250 lbs. Add the ice build up and a can of fuel and you will need the heavy springs. Because of the increased width due to the diameter of the metal mine rubbed lightly on the upper track/idler wheels but it was not a problem, they wore in - in about 2 miles. I run a 06' SB.
So it sounds like I should get either the .375/47's or the .405/77's. Does the angle of the .375/47's increase the tension, thus helping preload? Which has fewer fitment issues and is best for my lard?
Fatty, The .375/47's are a direct swapout and fit. Read the link that Guido posted above and you will probably get more info than needed. Here is a post from Curt at FTX Motorsports in that thread:
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
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
M
Mech Engr
Well-known member
springs
Hey fatymatty,
I just went through this two weeks ago and have the exact same sled as you and had the exact same problem. I researched this subject to death here on this forum. Here are the facts:
1. The sled came stock from the factory with .359 77 degree angle springs Polaris P/N's 7041629 and 7041630. These are the medium duty springs.
2. The .375 47 degree angle IS NOT a direct replacement because the angle is decreased but they will work great! How do you know you ask...because that is exactly what I ended up with and I am about the same weight as you. I have put aorund 200 miles on mine and couldn't be happier. Yes you are absolutely correct when you ask about the decreased angle causing a preload condition which makes them stiffer. The Polaris P/N's for these are 7042079 and 7042080 and don't forget to add the color code at the end or the part number or it won't come up. The color code is -067 for each P/N and specifies black. If you have a little time to wait you can get them at Dirt Cheap Snow for $72 each and receive free shipping. I couldn't wait and paid the $83 retail at my dealer.
3. The .405 77 degree will work too but may be a little stiff...not sure.
Good Luck!!
Big John
Hey fatymatty,
I just went through this two weeks ago and have the exact same sled as you and had the exact same problem. I researched this subject to death here on this forum. Here are the facts:
1. The sled came stock from the factory with .359 77 degree angle springs Polaris P/N's 7041629 and 7041630. These are the medium duty springs.
2. The .375 47 degree angle IS NOT a direct replacement because the angle is decreased but they will work great! How do you know you ask...because that is exactly what I ended up with and I am about the same weight as you. I have put aorund 200 miles on mine and couldn't be happier. Yes you are absolutely correct when you ask about the decreased angle causing a preload condition which makes them stiffer. The Polaris P/N's for these are 7042079 and 7042080 and don't forget to add the color code at the end or the part number or it won't come up. The color code is -067 for each P/N and specifies black. If you have a little time to wait you can get them at Dirt Cheap Snow for $72 each and receive free shipping. I couldn't wait and paid the $83 retail at my dealer.
3. The .405 77 degree will work too but may be a little stiff...not sure.
Good Luck!!
Big John
Perfect, thanks everybody!
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