Harley-Davidson motorcycle engines have been modified for light aircraft use. An HOAE version by an unknown builder is listed here. Also, see Long and Pickle.
O-37 -- { N/A / N/A / 37} / {N/A / N/A / 606}
2cyl; N/A; 9hp@N/Arpm; N/A; Wt = N/A; TC = none.
Ignition type not given.
Ae39.
Applications: None found.