The R80ST was the street-only version of the R80GS. It had slightly different styling, and the seat was slightly lower. It used the same air-cooled boxer twin engine with a dry clutch that put out 50hp at 6500 rpm. The 5-speed tranny drove the rear through the same Monolever shaft drive. Wheels were 19″ front, 18″ rear, for the street.
The ST was only made for 3 years. Reviews in Cycle World and Road Rider were positive. It was used in some European countries as a police bike, but did not find great success in the US. I think it was probably that rear fender profile that did it in…
This particular ST shows 79,750 miles, but the owner has records from a recent final drive rebuild, as well as some work on shocks, seat and tank. Tires are decent, and it runs well. You can find it listed for sale here on Craigslist for $4,000 in Atlanta, Georgia.
Sources:
Motorcycle Classics
Total Motorcycle
MCS