Radian 600cc Cafe Racer by ZDR Custom Moto.
The YX600 Radian is a sport/standard motorcycle manufactured by the Yamaha Motor Company between the years of 1986-1990.
The YX600 Radian chassis received less high performance components than its race-bred relatives in order to make the machine more affordable for the general riding community.
Some of these features included twin rear shock absorbers, rear drum brakes, and the lack of performance fairings, lending the motorcycle's appearance to the increasingly popular "Naked bike" styling at the time.
Info from Wikipedia