The '84 just needed a few years (30 lol) to sort out the set-up ;-) l think the 480 worked due to its shorter stroke; believe it or not, l think the '81 450 was a great bike, regardless of what some press said, its main problem that l thought when l owned one was the weak crancases would implode regularly. First time l ever won prize money was on a 450 back in '81. :-)