Any W-arm failures on the RS?

[garserio]

i hit a nasty bump last winter....enuff to break 2 bones in my spine. no breaks in the suspension......but look at the tunnel :shock:

http://www.imagetex.com/albums/userpics/10176/normal_ICE DAMAGE 002.jpg
http://www.imagetex.com/albums/userpics/10176/normal_ICE DAMAGE 003.jpg


OUCH!!! ILL NEVER BE THE SAME 05 vector....one tuff skid!!!

DUDE! That just happened to my sled this week at Tug Hill, NY. We were riding 2-3ft bumps at around 50mph and my header-to-muffler joint broke free and the same rear tunnel wrinkles occured.

I am going to fabricate some strengthening plates out of aluminum to rivet in that area... I'll keep you posted.

Not that I'm happy about your damage, but it is good to know that my problem is not unique.

Regards,
Greg

 

[garserio]

not a dent....its "kinked" on both sides....when the suspension bottomed out....the weight of the muffler caused the tunnel to kink.

Genesis, I totally agree with your statemnt about the muffler weight causing the kink. When me and my buddy were looking at the loose muffler connection, we discovered the tunnel damage. Of course, the whole ride home we were "theorizing" what the hell caused it and came to the same conclusion that the muffler weight is just too much for the tunnel to handle when you start airing out the sled.

My buddy calls it "oil-canning"

I think the tunnels on these 4-strokes are weaker than the old 2-stroke tunnels becuase the whole center area is missing to clear the exhaust pipe. Then you add all the extra weight of a muffler and it's a recipe for disaster escpecially for aggressive riders like you and myself. It really makes you wonder if the Nytro is going to hold up. Hopefully the wider floorboards on the Nytro have other strengthening features to prevent this from happening.

Anyhow, a nice set of custom aluminum plate stiffeners in that area should do the trick.

I'll take pics when I'm done...

 

[garserio]

OK, now back to the topic... You've seen Genesis' pics of his kinked tunnel and I have the EXACT same damage.

These kinks come from riding HARD, really HARD... HARD enough to kink a tunnel, BUT not hard enough to break the W-Arm.

I even put a 157# spring on the center shock (Stock is 104#) which stresses the W-arm even more. My W-arm is absolutley perfect even after the abuse of a HARD ride that can kink a tunnel...

The old Proaction W-Arms were made from square stock. The new Proactive W-Arms are all tubular which is much stronger. Plus the diameter of the tube is quite a bit larger than the diagonal of the old square tube style. I think Yamaha finally got the W-Arm right on these new RS sleds...

There is always a weakest link, so when you solve one, you just shift the problem to a new location. Obviously the rear of the tunnel is the new weak link for the new Proactive suspension, but hey, at least your W-Arm will last!