Having owned a number of these, I suggest you stay away from them. While they were good bikes when new, there is an endless list of things that go wrong with the older Honda's.
The camshaft rides in the aluminum head, without any bearing. While this is typical today, years ago, the methodology was not good. In other words, it is very likely the head is worn out. Along with the cam and followers. Even with a new head, cam and followers (about $1000 new) you still have an old bike.
The Rear shocks were junk, and the seals are by now rock hard. Good luck finding some quality replacements for less than 300 bucks. The forks were just as bad.
Today, you could purchase a Chinese copy of that bike and you would be getting a much higher quality bike. They really were that bad.