Manufacturer Yamaha Motor Company Production 1986 — 1990 | Parent company Yamaha Class Naked bike (standard) | |
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Engine 598cc, air-cooled, DOHC, inline-4 | ||
The YX600 Radian is a sport/standard motorcycle manufactured by the Yamaha Motor Company between the years of 1986-1990. The Radian came equipped with a slightly detuned version of Yamaha's 598cc, air-cooled, inline-4 which was used in the Yamaha FZ-600 Sport Motorcycle (grandfather of Yamaha's FZR series of performance bikes), and initially designed with 528cc for the 1981 XJ550 Seca and Maxim then in 1984 the bore, stroke and carburetor size were increased for the Yamaha XJ600/FJ600 sport bike. In 1986 the engine was fitted with smaller 550 style carburetors to fit between the frame rails in the Japanese FZ400 chassis and introduced as the FZ600 which was produced until 1988.
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.
Although the Radian's powerplant had slightly less top-end performance than its racing counterpart, the Yamaha FZ-600, it was noted that the machine's mild detuning contributed to a stronger mid-range powerband, and that the bike could pull away from an FZ model during short distance testing. Zero to 60mph acceleration tests of under four seconds are not uncommon with the YX600 Radian.