My 84 interstate runs gr8 untill I hit fifth gear then it just sits there. My buddie has a 89 1500 and he runs into the same wall in fifth gear. Is there some kind of thing done to these bikes so they dont pull in fifth gear? I`m talking right between 95 and 100mph they run out of pulling power. Is this a thing that all wings experience? Input would really be appreciated. My buddie and my have been tryin to figure this one out. Thanks alot guys.