Bent tunnel/rear suspension brackets

[CO 2.0]

So I bent the tunnel at the rear suspension brackets. The rails are straight. I didn't really hit anything that hard on my track to do this. If anything my rails should be bent. I had the additional cross brace in rails added. It was ever so slighty bent. In the process of installing bmfab limited boards when I noticed this. Was able to bang it back straight. Hopefully these boards add strength there.

 

[FCR112]

Ahh crap, I usually follow suit
With ur carnage except for all those cat engines. Did you bottom those exits really, really, really hard?

Also throwing out the obvious question which is "did anyone jump up and down on top of your tunnel holding 40lb Dumbbells in each hand?"

And the not so obvious of "did polarry finally make the tunnel so weak that the weight of the sled could possibly bend it when we have to roll the sleds over to get unsticked???"

 

[CO 2.0]

I did bottom the exits today, and hit the track/rails near that area. But it didn't seem that bad. Have hit stuff much worse on every sled ive owned since 2004 without tunnel damage with this minimal of a hit. Have 6 click on the exit rears. Will do more now, and crank the spring up a couple turns. I didn't get bucked, so im kinda stumped on this one. I've rolled the sled over a bunch this year but I don't think that's what caused it

 

[CO 2.0]

Anyone know of aftermarket bracing for this area?

 

[429dhm]

Would these work?

http://www.firenice.us/product/axys-extreme-tunnel-reinforcement-plate

 

[ullose272]

Off topic. What rear bumper is that?

Sent from my SM-G900V using Tapatalk

 

[CO 2.0]

Will probably get those fire n ice braces. Noticed I cracked the brackets on inside of tunnel. Both sides. Thats the bmfab rear bumper

 

[ullose272]

Will probably get those fire n ice braces. Noticed I cracked the brackets on inside of tunnel. Both sides. Thats the bmfab rear bumper

That same thing happened to a guy on facebook, the sledderz group i think. I think he made new peices out of steel

Sent from my SM-G900V using Tapatalk

 

[ullose272]

I dont really see how the fire and ice plates will help if its breaking the inside bracket.

Sent from my SM-G900V using Tapatalk

 

[ZRP Engineering]

I dont really see how the fire and ice plates will help if its breaking the inside bracket.

Sent from my SM-G900V using Tapatalk

Those posted FNI braces are really long and encompass that entire area plus some so they should brace the damaged area really well to tie everything together

 

[ullose272]

Those posted FNI braces are really long and encompass that entire area plus some so they should brace the damaged area really well to tie everything together

Sure but it doesnt help the bracket breaking away.

Sent from my SM-G900V using Tapatalk

 

[ZRP Engineering]

Sure but it doesnt help the bracket breaking away.

Sent from my SM-G900V using Tapatalk

Why not? Put riviets on both sides of the break and through the new brace i cant think of a better repair than that

 

[ullose272]

Why not? Put riviets on both sides of the break and through the new brace i cant think of a better repair than that

maybe? i dunno it may make the tunnel stronger but doesnt really help the stock part that is allready fatigued. i think if the stock part didnt have those little cut outs the part wouldnt be weak in that area and wouldnt have this issue

 

[Dootimes2]

Not calling you out or trying to be a d&@k, but to bend the cross shaft and split the braces like that I think you hit a lot harder than you think. I have read a lot of your posts and think you are quite honest, but sometimes perceptions of how hard we hit things are much different from reality. I have hit stuff so hard I thought for sure it was going to be expensive only to find out there was zero damage. Then there has been the exact opposite scenario where I have hit something that seemed inconsequential only to discover later that I bent or broke something. Impacts are not always what they seem at the time.

 

[CO 2.0]

Ive hit stuff much harder on my tracks with no damage, and softer with damage. I bent rails on my 14 proclimb off a minor landing that was crooked. Just a bad angle and they bent. This was pretty centered to break both brackets evenly. Just a perfect hit. Felt like hit was directly below the brackets. Usually when I hit something hard enough to break stuff I get bucked off the sled or stop to check out if I damaged anything. With this one I thought nothing of it and just kept riding. Cross shaft I bent was the extra one I added, nothing else in skid was bent.

Gonna drop the skid out and get the brackets lined up again. Possibly weld the cracks or just add strips of steel there and rivet them on. Seems like a total pain to drill out all those structural rivets there to put new brackets on. Prob get the fire n ice braces, and along with the bmfab boards, it should make it pretty rigid there. Would love to hear some other ideas on a fix.

 

[ullose272]

Maybe sheetmetalfab will chime in or maybe pm him. He seems to know stuff and things

Sent from my SM-G900V using Tapatalk

 

[Sheetmetalfab]

We put braces similar to the bmfab bumper ones behind the rear suspension bracket early this year and we cut the flange off to reduce snow building up at the rear of the running boards.

A combination of making the tunnel weak right at that point and strong behind there caused us to reconsider as my brothers sled crinkled a little at that point. At the time we figured our chopping of the triangle section at the rear of the running boards was the cause.

We added a gusset on the inside of the tunnel so only the rivets would show on the outside and because the running boards and rear brace had the outter part well covered.

Any Sheetmetal shop can cut you some 3' long inner plates for 50-60 bucks. I used .080 aluminum 2024 t3

Then they don't need to be powdercoated (or expensive) and the sled still sheds snow in the foot stomp area. I think the small tab down onto the drop bracket is critical for lateral support.

$140 for flat plates is just wrong.

On a upbeat note my wrap is finished.

 

[ullose272]

There ya go! I figured he had something for ya

Sent from my SM-G900V using Tapatalk

 

[B&M Fabrications]

Polaris did it again, solid chassis design with a minor flaw that leads to chassis failure. This is the Achilles tendon of a sweet sled. They relief cut the inner plate in the highest stressed spot on it. It's also only .080 aluminum sheet as well.



Sent from my SM-G928V using Tapatalk

 

[nordicmike]

We lost a week of riding in the mountains when my friend did blew out his drop bracket. the best part? polaris doesn't manufacture just the plate... Luckily a mechanical engineer in the group was able to get one drawn up then a machine shop was able to recreate it. add some aftermarket beefier drops and some Fire and Ice tunnel braces and hes been all set since.