250 1980 klx 250 bogs down when revved up

I have a 1980 klx 250 that bogs down when revved up. It still runs and rides and will hit high rpms but when you really give it gas it just acts like it wants to die. I've already cleaned out the carb but the problem persists. Any help would be greatly appreciated as I'm new to this and don't really know where to go next.
When cleaning the carb did you remove and clean the pilot jet? The pilots have a small hole and sometimes when you think its clean, it isn't. I would check that out and make sure you are running fresh gas. Also check the filter in the tank, normally removing the petcock to drop it out.