Idling problems help!!!

[350]

My dad has a 450R and is experiencing idling problems.Could it have anything to do with valve seating?have checked all the small things like air-cleaner.etc(irratic idling).Would appreciate the help.Cheers

[450rrider69]

have u tried adjusting the idle. the little black knob by the choke.

[JIMTED79]

Dirty carb?