The Yamaha XS 650 was produced from 1970 to 1980 and in the US the last model appeared in 1984. The first model was named XS-1, followed by XS-1B in 1971, XS-1 in 1972.
YAMAHAXS-1 1970 - 1980 Specs
Type:
Air Cooled, Four Stroke, Parallel Twin Cylinder, SOHC, 2 Valves Per Cylinder