Everyone knows H-D for its historic V-Twin engines, and amateur historians know about the company’s single-cylinder motors that powered many early H-Ds. But did you know Harley also built Boxer motors?
The 584cc W Sport (1919-22) used an opposed-Twin engine, with cylinders arranged inline with its wheels, patterned on the British Douglas. Producing only six horsepower, the W was not especially fast, but its low center of gravity gave it nimble handling. The lightweight model did not sell in large numbers stateside, but it did well overseas, with production numbers totalling nearly 10,000. The WJ (equipped with a battery and coil rather than a magneto) was the first motorcycle to ascend Mt. Baldy.
Harley’s other non-V-Twin was the XA of 1942, built at the request of the U.S. Army which wanted the benefits of shaft drive. It used a 742cc opposed-Twin oriented in the BMW Boxer fashion. Production stopped at 1,000 when the Army concluded the XA was too expensive and that the 45-inch WLA V-Twin would do the job just as well.