Congrats to Jason Cormier, who was the first to identify this not-a-Harley as a Rikuo.
I’ve featured a Rikuo before, and the short story is that during the Great Depression, Harley-Davidson got creative with revenue sources to stay in business. One of their more interesting ideas was to license their name and designs to one of Japan’s first motorcycle manufacturer. Rikuo’s story ended in 1950, when they were acquired by Showa.
For more on Rikuo, check out this article on Motorcycle Classics.