So I have everything performance wise apart from the jets. Found a guy who will weld the muffler for $60 (NZ). Finding part numbers for the jets is proving a hassle. I'm following Jamie's thread, so looking for a #140 and #145 main jet
http://www.gz250bike.com/forum/showthread.php?t=551 And sticking with Stage 1. Needle clip is already moved. Can't do much until I have the jets sorted out.