Hi.I just bought a 1980 cx 500 custom with about 36,000 miles on it.I fell in love with the bike when I test drove it.The price was more than reasonable for a bike in excellent shape.The one question that I have is related to a problem while running in 5th gear at 5500-6000 rpm.The engine runs erratically.Call it a "dead spot" or hesitation.I can run through the other gears up to 7,000 rpm easily with no problems.Would a cracked air boot(one of the large rubber hoses running to the back of the carburetors)cause this? I put premium gasoline in the bike and have seen some improvement.I´m thinking that maybe the carbs need to be cleaned?Any ideas?