Fuji Heavy Industries.
At the end of WWII, the Nakajima Aircraft Company reformed as New Fuji Industries in 1945, and then Fuji Heavy Industries in 1953. In June of 1946 they produced the 'Rabbit' scooter which was largely based on an American Powell scooter. The 'Rabbit' was quite successful with over 500,000 sold and remained in production till 1968 when it was removed from the market to allow a manufacturing transition to full Subaru production which had started in 1958. Eventually the name was changed to Subaru Co. Ltd in 2017.
Many models of 'Rabbit' were produced in 90cc, 123cc and 199cc models over the course of production. All used a 2 stroke engine, centrifugal clutch with torque converter drive. Initial test models supposedly used the wheels from the tail of the Navy Galaxy aircraft as rubber in the immediate post-war timeframe was unavailable. The first model was the S-1.
There is an extensive Rabbit owner's club in Japan - one web site with a wealth of information is available at this link.
Fuji Heavy Industries also produced a motorcycle called the 'Hurricane' (originally called the 'King Dyna' in 1954 ) but as yet I have very little data about them. Production supposedly ran from 1951 to 1961 and included 248cc 2 stoke machines and a 348cc ohv single 4 stroke version.