Harley-Davidson 1924 JDCA 1208cc 2 cyl IOE 3610

Harley-Davidson 1924 JDCA 1208cc IOE v-twin frame # 24F13184 engine # 24JDCA 13718B

In 1921 the 989cc twin got a larger-capacity brother; both bore and stroke were increased to 86.97 and 101.6 mm which led to 1208 cc or 74cu capacity. The 1922 sales brochure made a big thing of the extra power: “The Harley-Davidson 74” Superpowered twin cylinder Motorcycle is a specially designed machine possessing tremendous power, superpower, a surplus of the might that enables it to conquer rough roads, sand and mud and iron out the steepest hills with ease. The brute strength of the 74”Superpowered Twin and its bulldog tenacity in tough going makes it the ideal sidecar machine, especially for use with the two-passenger sidecar (model 22QL) and where travelling conditions are the worst.”
The new “74” had revised crankcase halves and a new design cylinder and head. Model codes were FD with magneto and JD with battery-and-coil. The extra power provided was not spectacular: the 1924 989 cc J had a power output of 18hp @3,600rpm, and the 1208 cc JD delivered 20hp @3,400rpm. The JDCA specified battery and coil ignition and aluminium alloy pistons, that gave more power and less vibration. This engine churned out 22 hp and the JDCA was with a price of $345 the most expensive model of the 1924 range.
Incidentally, 1924 was not a good year for the firm: the losses amounted to almost $ 120,000 and the workforce was trimmed down from 2,500 to 1,000 employees. More than 6,000 machines were exported oversees this year, almost half of all Harleys manufactured. Some of the new features for 1924 were the box- shaped silencer, wider front forks and Alemite grease nipples. Harleys used to have only an internal-expanding brake on the rear wheel but as many countries had legislation that demanded two independent working brakes, export models got an extra contracting-band brake that worked on the outside of the brake drum and was initially controlled by a lever on the handlebars. Later models had two foot pedals for the brakes. The JDCA we present comes with full electric lighting, horn and tank top toolbox-mounted Weston ammeter. She is an older restoration in fine overall condition.