Carabon Fiber Yoshimura RS-5 Failure

[Off Trail Mike]

Just a word of warning for those contemplating installing a Carbon Fiber Yoshi RS-5 as an undertunnel or rear mount.....DON'T! Choose Stainless or Titanium.

I bought a new CF Yoshi about a month ago and after about 5 hours of total ride time, I noticed it getting louder. Looked back and saw this

....smoked the CF end cap too.

Tore it apart and the packing was barely discolored.

Both the Titanium and Stainless versions of the Yoshi RS-5 are bulletproof (I've run them for 2 years now), but the carbon is another story.

I would say it is probably best to avoid any Carbon Fiber mufflers. IMHO our sleds are closer to racing bikes in performance because we are always on the throttle, so there is a pile of heat going thru those mufflers, and its a pretty brutal duty cycle.

OTM

 

[YamahaRider10]

I have had mine under my MTX tunnel now for 800 miles with no issues so far. Did it come in contact with the track at some point?

 

[Off Trail Mike]

Nope:

I am running the muffler pretty much where the stock one is, and its protected at the bottom with an aluminum deflector.

The only other thing I can see is a poor packing job from the factory, and if that's the case, you really have to be REALLY careful with your rebuild schedule.

OTM

 

[kinger]

I have that exhaust as well on my apex and no issue. How often do you rebuild them? Is it hard?

 

[Off Trail Mike]

No. Rebuilding is removing a dozen rivets, removing the fiberglass packing and replacing with new. There is a youtube vidio on how to do it and you can buy the repacking kit from Yoshi.

I am thinking 2000 - 3000 miles between rebuilds, I've got that many miles on my Ti RS-5 and I'm going to rebuild it this summer. Again, even Yoshi says take more care with the CF mufflers, so maybe half that. Its just that if you have an issue, your $500 muffler is toast. Better safe than sorry.

OTM

 

[beeze455]

I am running a cf exhaust this year with no issues.

 

[kennyspec]

I have a cf handle muffler on my Nytro. I think it got too hot and the epoxy holding the carbon "stiff" has burnt off and now the muffler is super flexible.

 

[Alatalo]

I hate to say it, but I think this is related to the material and build quality of american made Yoshimura exhaust systems. I had them on loads of streetbikes and all of them - except for japanese built race stuff for factory Suzukis - were massive disappointments from a quality point of view. Also, I had an Akrapovic carbon silencer on my 09 RTX SE during a full season with zero issues.