It had been remodeled from the AT125 by making it have a center raised exhaust and a raised fender. It let down its fans, for it didn't adopt a 21-inch front wheel.
It takes in the know-how of the commercially sold moto-crosser model, CR250R. It combines the long stroke that is advantageous in torque and the RC valve of the exhaust device.
It was the first naked model that gained tremendous popularity since its debut. Its old-fashioned style did not change, although it adopted a metal tank emblem and renewed its seat and suspension in 1990.
Based on CB400SS, it enlarged its carburetor diameter, reduced the weight of the ACG, and changed the gear ratio of its transmission. It was a remodeled motard bike that mounted a RFVC engine.
The second model W/W had a new graphic design and new base colors: navy blue and silver metallic. It also standardly adopted an under cowl and a single seat cowl.
It was the first commercially sold model to mount the square-4 engine. It was the full-scale replica model that took in the technologies earned from the RG GAMMA racing model.
Like the 750, it adopted a double cradle frame, a forward 24-degree tilted engine, and a water-cooled oil cooler. The SP model adopted the Φ 35 slingshot carburetor.
It standardly adopted a rear suspension with a separate reservoir, which used to be the equipment of the SP model only. They've also released SP model and the SPII model.