TyGuy: "So I've been exploring exhaust options. Tried to test the waters regarding a performance exhaust that might mate up correctly. The muffler options out there will involve cutting and welding, both of which I have the ability to do. However, I was looking for a full system. I reached out to Venom directly to explore possibilities. While it is not currently an option, they indicated that they will be exploring this soon as an offering.
For now, cutting and welding a muffler with need to suffice. Stay tuned."
I can't remember what JerryHawk did to his exhaust but this thread is chock full of good info.
http://www.chinariders.net/showthread.php?t=26256