Harley-Davidson rarely rushed change, and it always knew the value of cubic inches. The history of the 45° F-head V-twin goes back to the original prototype twin of 1907, and by 1928 it was approaching its sell-by date. In 1922 Harley created the JD model by increasing capacity from 61 to 74 cubic inches. The result was a high-performance machine capable of outrunning almost any other vehicle on the road in the 1920s. Olive Green was the standard paint finish in 1928, but buyers could pay extra for colors such as Black, White, Cream, Police Blue, Coach Green, Maroon, Fawn Gray, or Azure Blue. No wonder these models were popular with police departments.
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| Harley-Davidson 1928 JD |
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| Harley-Davidson 1928 JD |
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| Harley-Davidson 1928 JD |
The single camshaft JD model was a high performance machine that consistently outsold every other Harley between 1923 and 1930. This was partly due to its popularity with police departments. Sporting riders who wanted even more performance could opt for the two-cam JDH model, with its race derived engine. When Harley dropped the big F-head twins and replaced them with side-valve machines in 1930, many riders considered it a step backward. At first, the new side-valves were slower and no more reliable than the trusty F-head.
SPECIFICATIONS
Harley-Davidson 1928 JD• ENGINE Inlet-over-exhaust, V-twin
• CAPACITY 74cu. in. (1213cc)
• POWER OUTPUT 18bhp
• TRANSMISSION Three-speed, hand shift
• FRAME Tubular cradle
• SUSPENSION Leading-link front forks
• WEIGHT 365lb (166kg)
• TOP SPEED 75mph (121km/h)
