The engine in Honda’s first product, the 1947 A-Type, had a displacement of 50 cc.
The A-Type was a small auxiliary engine designed to be attached to a bicycle, rather than a complete motorcycle in the later Honda tradition. It emerged in postwar Japan, when transportation was scarce and people needed inexpensive ways to travel. Honda first used surplus two-stroke engines, but after those supplies ran out, Soichiro Honda’s team developed its own compact replacement.
The A-Type was a single-cylinder, two-stroke engine and became known for the distinctive “Bata Bata” sound it made in operation. Honda began producing and selling it in 1947, before Honda Motor Co., Ltd. was formally incorporated in 1948. That timing is why histories often describe it as Honda’s first product, even though it was an engine for a bicycle rather than a full motorcycle.
The A-Type should not be confused with Honda’s first fully fledged motorcycle, the 1949 D-Type, also called the Dream. The 50 cc figure refers to the A-Type’s engine displacement, not the capacity of a later Honda motorcycle bearing a similar name.