Hey. I'm running a 1991 Formula Mach 1 617 that I picked up cheap this past summer. Up until then, I've been riding an old 81 Polaris Cutlass, so this 617 was a real upgrade.
Everything's been good on it so far, esp. the engine (only 4000 original miles on the entire machine when I bought it). One thing I have been going through, mind you, is trailing arms, all on the left hand side.
The mangled arm in the first picture developed from what was originally a small dent on the arm when I bought the sled. The dent in the second pic happened this past weekend. I just threw on my third trailing arm, second brand new, in less than two months!
I was checking out the arms on my friend's 97 Skidoo Formula 700 triple, and they seem to be made more solidly. The one's I have seem to be just empty metal tubes. The impact that destroyed the second one was from a small rock (2 inches high), doing about 20 mph. It was nothing.
Does anyone know anything abou these trailing arms? It seems they're not really made to do the job. Everything else on this sled is good, lots of power, but I'm afraid I'll hit another bump and have to endure another ####ty ride home thanks to these garbage PRS arms. Does anyone else have any similar experiences with these things?

pic #2

Is the rest of your suspension moving on that side? Thousands of miles have been run on that PRS suspension so you have somthing not working right. I'd take a closer look at the shock and linkage....

Sunshine

That second photo is a clear case of hitting something very solid with a ski. If you have steel skis, I'd expect it to be bent, too. I ran several of those sleds over the years and never had a trailing arm bent like that. Then again I never hit any rocks. A 20 mph run that stops your ski cold will bend ANY trailing arm for sure, just like your photo...that's an awful lot of force to bring to a dead stop with a piece of thin tubular sheetmetal. If you don't run into rocks I bet they don't bend anymore:) ...duh.

Originally posted by gfid@Feb 2 2005, 04:20 AM
Hey.* I'm running a 1991 Formula Mach 1 617 that I picked up cheap this past summer.* Up until then, I've been riding an old 81 Polaris Cutlass, so this 617 was a real upgrade.
Everything's been good on it so far, esp. the engine (only 4000 original miles on the entire machine when I bought it).* One thing I have been going through, mind you, is trailing arms, all on the left hand side.
The mangled arm in the first picture developed from what was originally a small dent on the arm when I bought the sled.* The dent in the second pic happened this past weekend.* I just threw on my third trailing arm, second brand new, in less than two months!
I was checking out the arms on my friend's 97 Skidoo Formula 700 triple, and they seem to be made more solidly.* The one's I have seem to be just empty metal tubes.* The impact that destroyed the second one was from a small rock (2 inches high), doing about 20 mph.* It was nothing.
Does anyone know anything abou these trailing arms?* It seems they're not really made to do the job.* Everything else on this sled is good, lots of power, but I'm afraid I'll hit another bump and have to endure another ####ty ride home thanks to these garbage PRS arms.* Does anyone else have any similar experiences with these things?
397262


If you are buying Dennis Kirk aftermarket arms they are absolutely garbage as far as strength. They are cheesy thin guage material that will rust from the inside out. The Factory Ski-Doo ones are way stronger and can survive a good smack off of "mr. tree". The are more money than aftermarket ones, but you get what you pay for. Trust me there is a big difference in quality.
Rich

Same goes for Kimpex trailing arms available at Royal Dist. They are not as strong as OEM. Try to find a used set. They're chrome moly alloy.

Originally posted by Thumbdoctor@Feb 2 2005, 01:20 PM
Same goes for Kimpex trailing arms available at Royal Dist. They are not as strong as OEM. Try to find a used set. They're chrome moly alloy.
397433



Are you serious :lmao:

Here is my aftermarket trailing arm as you can see the metal is quite sturdy :crazy: and tack weld are better then solid welds :huh:

Hey, craze1cars, I'm not in the habit of hitting rocks either. But when it's stuck deep in the trail, and the two people in front of you go over it with no difficulty, it is a bit suprising when you see what it did to YOUR sled.
Someone mentioned the ski. Believe it or not, the ski was not hurt or bent at all. And that's after it flexed up and took a chunk out of my cowling as well. It's seems the trailing arm absorbed all of the impact on that little escapade.
I have no idea about the arm that was on there when I bought it, but the second one that got bent by the rock was an original. I picked it up from a used parts place. The one I just put on their is a Kimpex arm. Yes, Thumbdoctor, from Royal Dist.
It seems to be good so far, but we'll see when I run over a chunk of ice on the lake doing 100 mp/h. :hallo1:

never had any problems with oem arms. go to a sled junkyard and get a good oem used one. can of gloss black paint and your all set.

Originally posted by FreezerBurnt@Feb 3 2005, 11:56 PM
Are you serious :lmao:

Here is my aftermarket trailing arm as you can see the metal is quite sturdy :crazy: and tack weld are better then solid welds :huh:
398089


Hey FB,

That's a suitable place to photograph those after-market trailing arms. On a garbage can lid :lmao:

Be real carefull crossing railroad tracks with those after-market arms, as soon as the ski carbide catches the track, boom, ther goes another one !!!

I took out an original on my 91 Plus crossing a drain cover. Carbide caught slightly and boom, arm was out 45 degrees.

They do seem to be fairly fragile as I couldn't believe it bent. I was putting along with my daugther on board crossing the road.

You can toughen them up significantly by filling them up with expanding foam like you would use around your doors at home. Makes them tough as nails. Downside is if you really whack something then your looking at tunnel damage as the arm won't give at all. This trick was used on early racing sleds to get the arms to last.

If you want tough - foam them - as long as you are aware of the downside.

Hey if your looking for one i could sell you one, i also live near orillia ontario. pm me and well talk.

Thanks for the tip Scott. I've never heard of using foam like that!. Great info from everyone! These arms just seem pretty flimsy in comparison to other stuff on the market. Sure they're only $100, and if they absorb all of the damage in a crash instead of my tunnel or skis, great. I was just wondering...