1921 Harley-Davidson Model WJ Sport Twin Motorcycle

Engine: Horizontally-opposed, two-cylinder, four-stroke, air-cooled
Displacement: 584 cc (35.64 ci)
Bore & Stroke: 69.9 x 76.2 mm (2.75 x 3 in)
Power: 4.5 kW (6 hp)
Transmission: 3-forward, manual
Weight: 120 kg (265 lb)
Original Cost: C $462 (estimate)

The Sport Twin W/WJ motorcycle was built from 1919 to 1923 and the flat-twin engine design was a radical departure for Harley-Davidson. They were easy to start, smooth running and dependable. Because they were also lighter and easier to manage than many motorcycles available at that time, Harley-Davidson hoped they would find a market among newer riders who just wanted simple personal transportation. These machines proved much more popular in Europe, England and Australia than in North America. Due to poor American sales, production ceased in 1922.

When the Sport arrived in mid 1919 only acetylene lights were offered. The option of electric lights began in mid 1920. The Sport introduced the gear driven primary and wet clutch to America, however these features became famous when featured on the Indian Scout, after the Sport died out. Intake and exhaust manifolds were cast together throughout Sport production. At the time it was thought that heating the intake charge aided combustion, but cooling the intake has since been found to aid efficiency.

Chronology:

1903 - William A. Davidson, Walter Davidson Sr., Arthur Davidson and William S. Harley founded Harley-Davidson in Milwaukee, Wisconsin, USA.
1904 - Prototype machine raced in Milwaukee, Wisconsin, USA.
1905 - Started producing a limited number of motorcyles.
1906 - Harley-Davidson built their first factory.
1907 - Production increased and introduced their V-Twin prototype.
1911 - Introduced their improved V-twin model.
1912 - Introduced their patented "Ful-Floteing" seat.
1917 - Started producing bikes for the military and also launched a line of motorcycles aimed at the domestic market.
1920 - Harley-Davidson becomes the largest motorcycle manufacturer in the world.
1921 - Otto Walker, riding a Harley, set the record for the first motorcycle to win a race at greater than 160 km/h (100 mph).
1929 - Harley introduced the Model D - a flat-head V-twin aimed to compete with Indian and Excelsior. Vivian Boles drove 5,000 miles acoss the United States and Canada on a Model D.
1929-1933 The Great Depression caused sales of motorcycles to plummet but Harley-Davidson still continued to produce motorcycles.
1934 - Harley-Davidson unveiled a new line-up of motorcycles.
1936 - Knucklehead engine models introduced.
1939-1945 - Harley produced a large number of motorcycles for military efforts during the Second World War.
1969 - After years of financial troubles, American Machine and Foundry (AMF) buys the Harley-Davidson Company. To make the company profitable, AMF streamlined production and slashed the workforce, causing sales and quality to decline.
1969 - Stan Reynolds purchases this motorcyle from Washington State, USA.
1981 - AMF sold Harley-Davidson and the new investors changed operations, adding new technologies and improving quality and slowly growing the brand repuation.
1984 - Stan Reynolds donates this to the Reynolds-Alberta Museum.
1990 - Harley introduces the Fat Boy motorcyle which became the industry leader in the heavyweight motorcycle market.
2003 - Harley-Davidson celebrates their 100th anniversary.