I have a 1986 Yamaha Blaster the problem is that it was popping under load so it was rebuilt.I turned the pilot screw as the book states 1 and half turns out. The problem is now that it is hard to start when it does get going the engine starts to race up very fast where I have to kill it. With a little adjustment on the pilt screw the engine ran ok but stalls and I have to wait a little before starting it up What should I try next?

 

check the reeds. then take the the carb out and take it apart an see if you have any parts that broke or came out of ther spot. if u need any parts, go to www.vitosperformance.com. u can get some carbon reeds and a carb rebuild kit for under 100.

 

I know this is a dumb question but i think its your problem. Did you turns the piolet screw all the way in before turning it out?