(1955 / Production Model)
This was the deluxe version of the YA-1. Its features included a slightly bigger (by 4cc) 2-stroke single-cylinder engine, a black-painted chassis, chrome fuel tank and a battery case, giving it the quality look and feel of a higher grade model. With the chestnut red YA-1 known as the “Aka-tombo” (Red Dragonfly), the YB-1 came to be called the “Kuro-tombo” (Black Dragonfly).
- Overall length × width × height: 1,980mm × 660mm × 925mm
- Weight: 95kg
- Engine type: Air-cooled, 2-stroke, single-cylinder, 127cm³
- Maximum power output: 4.3kW (5.8PS) / 5,500r/min
- Maximum torque: 13.9N･m (1.42kgf･m) / 5,000r/min
- Price: ¥145,000
*All figures, etc. in a model's description or specifications are from when the model was originally released.