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.