I took the silencer off of my 03 z about 6 months ago. Is that a bad thing to do?? some yamaha mechanic told me that i could float a valve but i think he is full of ****. What do you guys think. Also i am starting to hear kind of a distinct backfire when decelerating, any idea what that could be. i work on cars and kind of new to the quad maintence. any input would help

 

That guy isnt full of ****.

 

Valve work time for you. Four strokes need back pressure to run, just like two strokes, but not as much. The mechanic was telling you the truth. I'm suprised the problems havent started earlier.