Yamaha was now already a volume production brand and the second generation of the 250 cc model had to be more modern. It received a pressed steel frame, like the YA2. What you can see from the sketches is that because of the "volume" of the frame there is little space between the cylinders, but for the battery and other electrics there is enough space. Lower left is the production version of the YD2, which appeared in December 1958. Neatly in black with a chromed fueltank it also had a downtube to the crankcases. It measured 1900 mm long, the wheelbase was 1270 mm and weight was 140 kg. Reasonably light in comparison with its competitors. The engine developed 14,5 hp and the YD2 was the first Yamaha to be exported to the USA. It was also sold in Mexico (CKD manufacture) and in Europe 40 were sold to the Netherlands (and a few to France). The YD3 (lower right) was similar to the YD2, but slightly more luxurious with larger brakedrums, whitewall tyres, 17 hp (!) and it was the first Yamaha with the 3 tuning forks proudly on the fueltank. (You can "click" on YD2 and YD3 to see my bikes.

Yamaha YD2, Feb. '59; YD3, Nov. '61