how to prevent w-arm (front pivot of rear suspension) from breaking again

wisconsin

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south central wisconsin
I broke the w-arm in 4 places the other night going between two fields. :o| The dip was only about a foot deep that I hit. I am going to weld it up, but I am wondering how to prevent this from happening again. I have heard from another owner that these sleds are notorious for having this problem. Thanks for your help.
 
When you weld it up, put in some gussets like in the picture.
 

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I think allot of this W arm issue people are having is not having the suspention set up correcly.

If you are set up to soft you will bottom easily promoting breakage.

In the early years i had my SX set up to soft and broke the W arm and front shock. My FRA was on soft.

Now with the new parts installed and the just putting the FRA in the center I have been all good for the last 6 years. Even my bump stops look great.

Tod
 
well, I have just gotten the sled and didn't adjust anything yet. I have been told to crank the front shock springs all of the way up and adjust the front shock of the rear suspension to the middle of the threads. Any suggestions? I can't remember offhand if the rear suspension-rear shock spring is adjustable? The previous owner told me that he put adjustable arms on the rear of the sled that you can turn by hand. They have anodized blue metal on them I belive. any setting suggestions for these as well? Thanks again for your time! It looked to me as though the front springs and front shock of the rear suspension were set correctly before the w-arm broke. I didn't notice any bottoming out, but after it broke I sure did when I hit any significant bump on the way home! :o|
 
if you have those transfer rods crank down for more transfer you will not link and crash the front arm every time...as Tod said, it is due to not having the skid set up properly.
 
I have my front arm spring pretty stiff,the back spring i have 3 from max.I ride my sled pretty hard and have hit more than a few big ruts and havent had any problems so far.
 
I ride hard as well, and I like to ride with my girlfriend on the back too when she can go. I don't mind having it too stiff because I am used to riding my old 1995 polaris xcr 600. I just don't want to bottom out and I sure as hell don't want to break that w-arm again! She weighs about 118 with street clothes on (not riding gear). I weigh 175 in street clothes. so, together that's 288 without the couple of extra pounds of winter gear each...maybe 300 then total with winter gear? Let me know how this affects your recommended suspension settings folks. I wish there was a quicker way to adjust the suspension when a passenger jumps on.
 
I should also crank the front springs up so that almost all of the threads are showing? That is what I have read to do. 1/2" of threads left hidden is what I have been told for the front ski shocks. This sled hooks up terribly as it is now. Stock track=.92" lugs...a few torn off/worn lugs..not many, and only on the outside right row...no pull throughs, no rips or tears, the other lugs show very little if any wear . 144 studs worn down...need new ones, but would like to get a deeper lug track instead. Local Dealership.in jefferson,WI..www.RockRiverPowersports.com.... parts guy said to just re-stud factory track and it will hook up well. 1.075" studs....196...because I am looking to put pipes/jet/clutch when I find a decent deal on that stuff.
 
Welding

I have repaired 5 w-arms and I think the w-arm is strong enough without the gussets. None of them have cracked again, I think they are not good welded from factory. the material is to thin beside the weld so it cracks. Also look at the lower end of the shock I had problems with this part also. It cracks at the welds and the pipe twists and break the shock.I sandblast the welds so its easy to see any cracks, and easy to make good welds.
 
You need to keep the gap on the top side of the transfer rods tighter on the top side when you are sitting on the sled....take a picture of the rods with no weight on the sled and I will be able to help you better.
 
Mrsled is right about the control rod gap, tighter gap on top means less transfer because the suspension couples sooner, which also means a stiffer ride because when you hit a bump the front and rear arms work together to resist bottoming. On my '01 sx 700R i have the center spring cranked almost all the way up with great results. It really helps to keep the front arm from bottoming, the sled transfers weight well, pivots quickly in the corners, and goes through bumps much better. FRA is in medium position, and the rear spring is set for a 50/50 control rod gap. Front springs are cranked about a half inch from the top, really digs hard in the corners. I simply love that setup, really works well.
 
I don't have a digicam to take pics, but I will:

1.. crank the ski shocks up almost all of the way
2.. crank the center shock up almost all of the way
3.. crank the rear shock to the middle
4.. where exactly should i crank the rear transfer rods to?
5.. Should the postions of the front of the rear shock be moved to a different hole? Remember that I do ride with two people on the sled at times. I do like to jump the sled (not 30 foot sno-cross jumps though). I really appreciate your feedback!
 
you may want to run the fra in the hard position then, which i beleive is the upper postion, that is the adjustment at the front of the rear shock. Set the rear spring for a 50/50 or 60/40 control rod gap. That thing will really ride stiff when you are alone though with the fra in the hardest position.
 
I think I will leave the fra alone for now and see if I bottom out with her on it at all. any ideas on exactly where to set the rear transfer rods or whatever they are called? I could do this stuff myself, but I don't know the symptoms/effects of adjusting each individual component and how they work in relation to each other.
 
the less transfer you run on the rods (smaller gap on top side of the control rod guide) the better chances your w arm will NOT break. The more transfer you run the more stress it puts on the w arm
 
so how exactly do the rear transfer rods affect the suspension? How does the "coupling" and "transfer" work exactly.....more gap at the top of the rear rods=?
.....less gap at the top of the rear rods=?
thanks again!
 


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