Mufler Bearings Part Two

While searching for a good place for my zerk fitting last night I noticed that although my muffler clearly has a screen type spark arrestor there are no stampings on the pipe for U.S.F.S. approval. Does this preclude me from being able to ride in natl. and state parks legally? It's not a real issue for me but I have been to several enduros where they checked for the stamp and I read all the time about this issue for other riders out west. There is a nice line about 82db for this particular muffler and the end cap mentions that it is a (screen type muffler) but other details are not evident.

I am not trying to stir up alot issues here I was just curriuos what makes for a legal pipe. Theres not alot of reasons to buy those high dollar Ti bearings if my pipe is illegal.

I am sure you will be ok. They know what stock looks like. They will know. Just dont tell them what kind of muffler berrings you have in there. Some cause micro spark. And one micro spark can start a fire. Just so you know. It happens in california all the time.


I would be careful in state and national forests without that stamp. I can almost guarantee that you will have some problems without the stamp.

I'd check your manual and call the dealer.

That's the beutiful part of the great state of TN. All public land closed!!! Does not really bother me one way or the other I just thought it was an interesting point. Why would yamaha go to all the trouble to choke my bike down to the point where my riding lawnmower is faster and louder and not get a USFS stamp for the boat anchor I mean muffler

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