i just got a 04 yamah blaster about a week ago and the PO said it just needed the carb cleaned out. it will start up and idle ok for a minute and then start loading up with fuel and die. if you give it WOT it will rev up to like 3k rmp and then start loading up but it will slowly raise rpm and then when you let off the gas it will return to a very rich idle . it runs good the first minute you start it up for the first time of the day. i have had the carb apart a good bit and have adjusted the floats to stock . i have cleaned every inch of the carb i can reach . i have the idle turned up a good bit so it will some what maintain an idle . im completely out of ideas.