mmm..the 450 we had went great on the dirt track but was a bit of a handfull elsewhere..just stick it in 4th and forget it was the best bet
it did have gearbox issues, namely a broken output shaft when purchased, didn't we have some fun trying to find a replacement at the time! $$$$ ching ching!
..mid 80's after the rebuild it was sold for about $800 :'( lookin' for some more pics..no expert but they did have a few issues with the swingarm also around the rear adjuster area..this carried over to the 250 RB's also but only due to poor or no maintainance. Been trying to drag my mate out to a QVMX meeting on his 250RB..it's a Honda I really do like riding if given the opportunity