The YS 140 FZ muffler mounted on my DP Ulty opened up like a tuna can. Has anyone seen this before? [X(]

Running hard, it got hot, very hot. DId you have it in the air stream? Get a pitts muffler or put a hose on it and extend the exhaust to the rear. The hose will make it loud but it will do until you get a replacement.

Yup, muffler was in the airstream and the engine gets pleanty of cooling. I've already decided to get a Pitts muffler for it. It's too darn cold to be flying much more this year so it will be ready by warm weather. Is it Spring yet?

Thanks

If the muffler was in teh airstream, I would make sure that you understand what happened.
It should not get that hot or have any heavy back pressure. Did the insert (restrictor) plug up with something?

I have never had any luck with YS mufflers.
My FZ 1.20 muffler broke of in flight...at the bend in the header pipe. Clean break!
I was just so angry with the quality that I carried on flying through out he day making one hell of a lot of noise.
Any complaints should be forwarded to YS etc.
Yours is just wonderfull, never seen anything like it.
Send it back and make some noise yourself!

Jep had the exact same problem.The motor was only running in and had never gone to full throttle so I dont believe its a overheating problem.My thaughts are that the metal restrictor(washer) inside the muffler simply spunn around cutting its way through the case..Pity as it was the quietest set up I have ever had.