03 trailboss 330 runs fine till you nail it then it boggs and won't rev. I've cleaned the carb and everything looks good.Runs ok till half throttle but then has no power and boggs really bad. doesn't matter what clip position and it has plenty of spark.

 

Welcome to the forums.

Could be the vacuum slide sticking. How did the diaphragm look on the carb?

 

The diaphragm looked fine. the slide was kinda scuffed in appearance but still smooth.