Lot 317: 1917 Harley-Davidson 74cu in V-Twin
1909 marked the appearance of Harley-Davidson’s first v-twin, though it was not until the adoption of mechanically operated inlet valves in 1911 (replacing the ‘atmospheric’ type inherited from the single) that production really took off. Known by the soubriquet ‘pocket valve’, this inlet-over-exhaust engine - built in 61 and 74ci in capacities - would remain in production for the next 20 years. The Harley single’s transmission arrangements - direct drive by means of a leather belt - were continued at first on the twin, but the need to make better use of the engine’s power characteristics, particularly for sidecar pulling, prompted the introduction of a two-speed rear hub for 1914, by which time chain drive and a proper clutch had been adopted. Later that same year a conventional, three-speed, sliding-gear transmission with ‘step starter’ was introduced on the top-of-the-range version of the twin which, with full electrical equipment, was listed from now on as the Model J. Two important developments in the twin’s evolution occurred in 1916: the most immediately obvious being the adoption of a gently curved fuel tank which replaced the slab-sided tank used previously. Inside the engine, the cams were altered from two-lobe to four-lobe, making alterations to valve timing - previously achieved by reshaping the followers - that much simpler.
This modified but unrestored Harley-Davidson 74ci in pocket-valve twin has the olive green colour scheme, adopted from 1917 onwards, that superseded the original all-grey finish. The pocket-valve twin was the choice mount of ‘Kokomo’, a Bay Area ‘outlaw’ biker that the Hell’s Angels reputedly fashioned their style around.
Sale of Collectors' Motorcycles|
Bonhams & Butterfields, Petersen Museum, Los Angeles, CA
|Hammer Price (inc premium)||$16100|
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|Engine - cylinders|
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