Harley-Davidson stunned the world when it unveiled its EL 61, better known as the Knucklehead, on November 25, 1935. The overhead-valve technology was impressive at a time when sidevalve engines were the order of the day, and the engine formed the basis for all Harley Big Twins to follow, right through the Evolution engines of the 1980s and 90s. But what really grabbed enthusiasts’ attention was the styling of the new Harleys. The Knucklehead formed the die from which all future (more…)