Rear Tunnel Crinkling - My Repair

[garserio]

A few weeks ago, TY member, "Genesis" posted some pics of his Vector's rear tunnel damage. A week later, I experienced the SAME EXACT damage from a really hard ride up in Tug Hill, NY.

The rear of the tunnel develops a crinkle, or bending, right around where the rear bumper cover meets the running boards. I, and "Genesis" came to the same conclusion that the mass of the muffler causes this bending to occur when subjected to exceptionally rough riding.

I decided that my riding style is not going to get any less aggressive and the trails where I ride certainly aren't going to get more smooth, so I made up a pair of strengthening plates for the weak area of the Vector's tunnel. These plates were fabricated and mounted to both sides.

The aluminum is 0.120" Thick and I used S/S Structural Rivets which are the strongest blind rivets available.

I cut the plates out with a jigsaw and sanded them smooth.

Check out the pics...

 

[Oak Hill]

Nice work!

 

[Tork]

Good craftsmanship
Weight could be it. Muffler or all the ice that can build up?

 

[RedRX1]

That is strange, the crinkle is past the rear axle pivot point. Did you land on your tail? I find it hard to believe Snow and ice could cause this unless the track was bottoming against the tunnel.

 

[NY_Nytro]

Is the crinkle caused by bent up or bent down damage?

 

[twomorestrokes]

Looks great Greg!

 

[garserio]

That is strange, the crinkle is past the rear axle pivot point. Did you land on your tail? I find it hard to believe Snow and ice could cause this unless the track was bottoming against the tunnel.

I don't believe this is from snow and ice... I actually mounted a rear heat exchanger kit to eliminate the mud flap icing problem.

I didn't land on my tail either...

The fact is that the muffler is a very large mass to be hanging off the rear of the sled. When the #*$&@ end kicks around, the momontum of that muffler weight just tears apart the machine... and, of course, the one little area on the rear of the tunnel that is not plated/riveted/laminated to anything else is the weak point and the metal buckling occurs...

This is an oversight by Yamaha's structural engineers... For most riders, this won't happen, but if you hammer your machine through the bumps, expect the same damage.

After I reworked my whole rear suspension with a rear Ohlin, revalving, different spring rates, etc, I found that the machine could handle bigger bumps better, so I rode it to its new potential and apparently the tunnel couldn't hang... Now that problem is solved.

Let's see what I break this weekend!

 

[RedRX1]

I typically hammer through the bumps, to me it is a lot more fun than slowing down for them. I hop I don't have that problem!!

Nice job with the repair, it looks top notch.

 

[NY_Nytro]

I wonder if the Vector is weaker than the RX-1 in that section. You think someone over the 3+ years the RX-1 has been out someone would have had that happen. There got to be other mega hard riders out there.

 

[flyingpig]

So are you an A&P mechanic Garserio?

 

[garserio]

Well, my repair fixed the problem. I did a hard test ride yesterday and nothing bent. In fact the floorboards had a stiffer feel to them and in general, the chassis felt stiffer as well.

Here's the funny news about my reapir... I wasted my time fabricating parts. ..

My buddy pulled out his new Apex RTX yesterday and we were talking about all the potential problems he may have using my seld as the benchmark. We looked under the rear of the tunnel to scope out where his is weak and GUESS WHAT? Yamaha realized the problem and added a very nicely formed strengething bracket for the same area. It is a complex sheet metal stamping that would be very tough to fabricate without a stanmping die...

So, if you want to be proactive (No pun intended here), you might want to pick up a set of these brackets and all the rivets to boot...

FYI...

 

[garserio]

So are you an A&P mechanic Garserio?

I'm actually an engineer. I just like to wrench on things...

More importantly though, I like to make sure my equipment is robust enough so I'm NOT the guy who ruins a sled trip with a busted-up sled...

Then there was a time back in my teenager years where I was running a Jet-ski on a river and the engine died. 5 minutes later I was smashed up against the top of a 100ft high hydroelectric power dam holding on for my life... A simple dead battery almost sent me for my final swim! That experience kind of changed things for me in terms of maintenance and repair... (For all you TY members in MA & NH, that was the Merrimack River in Lawrence, MA)

 

[RSVECTORFREAK]

Very nice fabrication work there! I am going to look into those brackets and see if I can get a part number myself, I ride very hard myself so it's just a matter of time mine will probably do the same.

 

[apex yooper]

I was ready to suggest reinforcing in the tunnel, when I read that Yami did it.

 

[bluecheese]

This problem doesn't just happen when you drive hard. I went for an easy 200 mile ride last week on good smooth trails and now have a total of 1,650 miles on my vector. I looked at my tunnel last week after seeing the posts about it crinkling and it looked fine. I looked at it after my ride and it was bent just like in the pictures on this post. I went to the dealer today and complained and insisted that this should be covered under warranty to install some type of support brackets. I'm waiting to hear back from them tonight. This seems like a poor design and is simply not acceptable. If I bought a new car and a year later the fenders were caving in...it would certainly be covered under warranty.