The Yamaha XJ600 is a motorcycle manufactured by Yamaha. It is a relatively light motorcycle with top half fairing and around 72 bhp (54 kW). The XJ600 was built from 1984 until 1991, when it was replaced with the Yamaha Diversion/Seca II. In North America, the bike was sold as the FJ600. The 1984 Yamaha XJ600 and FJ600 were notable for being the first Japanese inline-4 motorcycles with a displacement of 600cc. They are also one of the first inline-4 motorcycles to use mono-shock rear suspension.