well i bit the bullet and got a motad 4 into 1 exhauastv foir for my 72 k1 500 from david silver spares. in installation was a snap and the bike runs better with it. only complaints where that i wish they supplied more lock washers for the mounting bolts and the muffler bracket came with a place for a bumper for the center stand..but no bumper. no biggie i put one on but i am finding even though the muffler mount is stanless it will need to be stiffened up since it keeps bending everytime the centerstand contacts the bumper. a .063 stainless angle will fix that. all in all if any of you have been thinking about one of these i highly recommend it. very quiet if that what you like.