1934 Harley-Davidson 500cc CAC Speedway Racing Motorcycle

• One of the rarest Harley-Davidsons of all time
• Only a dozen or so made by Harley-Davidson
• One of only nine known to survive
• Present family ownership since at least the 1970s
• Highly original and unmolested

Having started in New Zealand and Australia, speedway (or dirt track) racing was increasing in popularity on both sides of the Atlantic in the late 1920s. Fortunately for Harley-Davidson, they already had in their line-up the 21ci (344cc) single-cylinder Model AA 'Peashooter', which proved supremely adaptable to this new form of motorcycle sport. Through the efforts of star works rider Joseph 'Joe' Petrali, Harley-Davidson would go onto sweep the board in Class A '21 cubic inch' races, while the Peashooter was also highly successful in the UK, Australia and New Zealand before it was superseded later in the 1930s by JAP-engined machinery.

'Smokey' Joe Petrali was a many-time AMA champion who competed in board track, dirt track and hill climb events, as well as making a successful land speed record attempt in 1937. The son of Italian immigrants, Petrali was born in 1904 and first signed for Harley-Davidson in 1921, riding the Milwaukee big twins on the board tracks. When H-D made one of their periodical withdrawals from racing, Petrali moved in 1925 to Excelsior where he assisted Chief Engineer Arthur Constantine in developing a new 21ci racer. When the Excelsior factory closed n 1931, Joe made his way back to Harley-Davidson.

With interest in professional flat track racing beginning to fade, Harley-Davidson sought to revive the sport by developing a new Peashooter-type machine for the 30.5ci (500cc) class, the engine of which had clearly been inspired by that of the British JAP. In his seminal work, Harley-Davidson – The Milwaukee Marvel, Harry V Sucher has this to say about the project: "...its development was largely the work of Joe Petrali, who designed and tested the new engine largely in his own time. He was encouraged in the effort by President Walter Davidson, who now hoped for a more potent machine to compete with the current crop of JAPs and Rudge Specials which had largely dominated flat track competition."

H-D's racing department went on to build around a dozen of these CAC dirt track machines. Unfortunately, the design was not without its flaws and early results were discouraging, though you would never have guessed from Harley's advertising: "The short track racers we are offering are the result of much study and actual trial by our racing department. Extensive tests were conducted on the West Coast on actual tracks with outstanding short track racing stars and in competition with the best of the foreign machines. Our experimental machines came through every test with flying colors. Improvements incorporated as a result of these trials will make these new racing models even better in power and performance."

To Petrali's chagrin, Walter Davidson cancelled the project before the CAC could reach production, ostensibly on grounds of its cost, and refused to pay Joe his promised $1,000 bonus. Today, the almost mythical CAC is one of the rarest Harley-Davidsons of all time, with only nine known survivors.

An amazing discovery and an extraordinary survivor, this Harley-Davidson CAC has been in a private collection since at least the 1970s. The vendor's father was a collector of fine motor vehicles but, unfortunately, we do not know how he acquired the Harley-Davidson. The knee hook has its original hessian fabric and the Lycette saddle appears to have been on the CAC since the early part of its life, while the worn tyres testify to the machine having been used. A possibly once-in-a-lifetime opportunity for the dedicated Harley-Davidson collector.
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