When this gorgeous, original 1930 Harley-Davidson DL rolled off the line in Milwaukee, the Motor Company was already feeling the squeeze brought on by the market crash the year before. However, be it through foresight or luck, Harley-Davidson set itself up well to weather the financial storm by developing a new type of engine, the economical and efficient sidevalve, in the years preceding the crash. Initially, the company used its lineup of lightweight singles as the testbed for its new sidevalve, or "flathead" engines in the mid-1920s, but in 1929, the Motor Company unveiled its first flathead V-twin with the 45 CI (750cc) Model D.
Since its creation in 1903, the Harley-Davidson Motor Company has built sturdy, powerful motorcycles on a foundation of IOE, or F-head type engines, a format that delivers ample torque and acceleration but is challenging to produce and service. Sidevalve technology existed throughout Harley's ascent to the top of the motorcycle market, but after its half-hearted experiment with the odd and unsuccessful Model W Sport Twin in 1919, Harley remained dedicated to its trusty F-head. However, motivated partly by Indian's new 350cc Prince lightweight model in 1925 and the smaller displacement preferences in racing, Harley relaunched its investigation of a sidevalve engine in 1926 with the Models A and B singles.
At the same time, Harley was pressed to develop a middleweight machine in the increasingly popular 45 CI (750cc) displacement following the success of Excelsior's Super-X and Indian's Scout. In 1929, Harley released a V-twin version of its new sidevalve, the Model D, utilizing the same chassis as its line of singles. However, the increased capability proved too much for the small frame and the Motor Company redesigned its new middleweight in the middle of 1929. The 1930 D series V-twins carried over the changes made by late 1929, including a new frame, new i-beam fork, new tanks, larger clutch, steering head lock, detachable, interchangeable wheels and a front brake. This high-compression 1930 Harley-Davidson DL was initially produced as a police patrol unit and remains in highly original condition. The same year that this gorgeous 1930 DL was built, the Motor Company also adopted the sidevalve V-twin design for its Big Twin models, ending the long run of Harley-Davidson F-heads and embracing the practical efficiency of the flathead as proven by machines like this exquisite Model DL.
