Hey all! I have a problem when switching into 3rd gear, the bike really bogs and I have to feather the throttle . First and second are ok but third is not good….haven’t even got it to 4th. Took the air filter off and no change. Back story….I purchased the bike from a friend, was sitting in a shed for 22 years. Rust EVERYWHERE..in the gas tank etc, cleaned the carb but may have missed something. Any ideas?