The first Harley-Davidson motorcycle to feature a clutch and gear shifter on the left side of the bike was the Harley-Davidson Model K. Introduced in 1952, the Model K was a significant departure from previous Harley models, which had the gear shifter on the right side. The Model K featured a foot-operated clutch and a tank-mounted gear shifter on the left side, making it more similar to the standard configuration used by many motorcycle manufacturers. This change allowed riders to shift gears with their left foot and operate the clutch with their left hand, which became the standard arrangement for subsequent Harley-Davidson motorcycles.