How did Yamaha start motorcycle manufacturing?

Yamaha has a construction class, which specializes in maintaining the company's machines and designing fixtures. The technical level of this department is quite high. Coincided with World War II, many military enterprises emerged in Japan. Yamaha is near Honda, and their construction team has started to produce engines. Later, it became Yamaha Engine Co., Ltd. independently from Yamaha musical instruments, but it still retained the original LOGO, but there are still differences between the two logos. The tips of the three tuning forks,