Yamaha XS650

The Yamaha XS650 is a mid-size parallel-twin motorcycle made by Yamaha. The standard model was introduced in October 1969 and built until 1979, and a cruiser-styled Special model followed in 1978 and stayed in production until 1985. When it was launched it had one of the most advanced engines in its class of large parallel twins, with engine and gearbox in unit construction and a crankcase split horizontally for easy assembly, at a time when most rivals still used pre-unit or vertically split cases. Its single overhead camshaft engine was lighter on revs than the British pushrod twins it competed with, and the engine was used in American dirt track racing by national champion Kenny Roberts. The first two model years, the XS-1 and XS-1B, were kick start only, and an electric starter arrived from the 1972 model year.