Just a shout out for Silent Sport exhaust packing. It is more of a thread than a blanket type, very easy to use! Pulled apart my Yoshi 4-1 can after a year of usage, and found the packing still in awesome shape with no appreciable gain in noise ( I have a db meter, originally 87db at 5' behind bike, crept to 89 db) previous blanket packing was 94 db at one years use. 30$ Canadian for a bag big enough to do 2 repacks plus a bit left over. Try it!