[4] The production of the Harley-Davidson in Japan resulted in large part from the United Kingdom's McKenna Tariffs modification of 1921.

In 1924 the Military Subsidy law allowed the government to subsidize certain industries in order to encourage domestic production.

Both Murata Iron works and Toyo Kogyo, later called Mazda, tried to copy the Harley-Davidson motorcycle and failed.

Having lost much of their overseas sales to the British Commonwealth nations, Harley-Davidson looked to Japan to make up for their losses.

The Road King motorcycle was improved and produced by Lin Ritsukawa, and Tsui Meguro under the Tokyu Kogyo Kurogane Company during World War II.

Harley-Davidson, through the efforts of Alfred Rich Child,[6] shipped tooling and personnel to Japan in the mid-1930s to build HD VL flathead (sidevalve) motorcycles.

However Sankyo, Rikuo's parent company, was reluctant to produce the new vehicles and refused to make this commitment.

Japan's government was becoming increasingly militaristic leading up to World War II and eventually suggested that Harley-Davidson employees, including Mr. Child, leave the country.

[7] Sidecar combinations called Type 97 were produced for military work in the Philippines and Manchuria during the Second World War.