1995 Johnson 30HP 2 cycle idles smooth; smooth at WOT, Rough in Middle

[777funk]

My dad has a 95 Johnson 30 Horse and it has a pretty rough range in the middle but low and high are great. What could his problem be?

 

[fireman57]

Give the carbs a good cleaning. Crap in a jet somewhere that is making it have trouble going from low speed to high speed.