Hey,
One other thing..
I am thinking of swapping the muffler to a packable fiberglass kind, and i took a look here:
http://www.650central.com/mufflers.htm
And it would seem that they do have mufflers with adaptors for 1 1/2 inches.
I was reading on here how someone was saying to weld a piece of galvanized pipe (etc ...), but is this really needed?
Take a look.