my strait pipe was a little loud for city riding. went to tractor supply and got a briggs and stratton muffler for $9 and a 1" strait thread end and a 3/4" to 1" addapter. was all together $14. when i got home i went to put it on and the inner linner came out and i thought why not mod it. i drilled half of the holes out twice the size. than welded it back together. ill see how loud it is when i get my bike reassembled.