Harris Matchless G80 Rotax

I just picked up an '88 G80 Harris Matchless (500cc Rotax single). Anybody here have any info on them? I get next to nothing online. The bike belonged to a friend who rode it to Mexico and back in 1994. Its been passed around amongst a bunch of my street riding buddies and now its mine. It was listed on Craigslist and he got 75 calls but I was second. The first guy didn't show up-probably sobered up.
Larry