A brother, Cabana Dan owns this bike. There were only ten built as prototypes to compete with the Whizzer kit motorbikes. Dan only knows of two and this is one of them. It’s been housed in the National Motorcycle Museum for years, but since they plan to close their doors, Dan is headed to Iowa to pick it up.
In the early years, the American motorcycle industry served riders with a broad range of machines including lightweight singles. But post-Depression most American motorcycles were at least 500cc’s and had a considerable weight and price tag. The price of a new Indian or Harley-Davidson could buy most of a new Ford or Chevy.
But the scooter niche, which began in the 1920s, offered a more affordable, convenient and lightweight alternative. American industry adapted, diversified and we saw machines like Salsbury and Cushman scooters come along and then the Whizzer, a power cycle built around a bicycle chassis. Not a new idea, the clip-on engine for a bicycle, but they served well here and abroad. In fact, Honda’s first machine post-World War II used a War surplus Tohatsu engines.
A Racine, Wisconsin engine and lawn mower manufacturer considered ways diversify its offerings. The Jacobsen research and development department built about ten prototype power cycles using one of their small two-cycle engines mounted high above the pedal crank on a standard bicycle. The idea was to offer a kit customers could install on a standard bicycle. They didn’t plan to sell a complete machine.
The January 1985 edition of THE COASTER, the newsletter of the Classic Bicycle and Whizzer Club of America, told this story: In 1951 about ten prototype kits were made by Jacobsen Manufacturing Company, Racine, Wisconsin, and installed on a range of bicycles. The Racine Explorer Scouts were engaged to test the new machines on a 1000-mile ride through Wisconsin and Michigan, followed by a truck with mechanics, factory staff and spare parts. Each Scout would be offered his test bike for $45.
But the rest of the story includes an employee, who apparently lost part of a finger in a drive belt accident, perhaps before a belt guard had been designed. The company cancelled the project and worked on a belt guard. Long time Museum supporter and motorcycle lender Dan Rognsvoog acquired this rare example. He enjoys that it’s a prototype, one of a very few likely still existing, and likes that it’s predominately original and has an interesting back story.
Knud Jacobsen, a Danish immigrant was a skilled woodworker and developed a successful industrial pattern making company, Thor Machine Works. Thor launched Jacobsen lawn mowing machines in the early 1920s. Commercial in capacity, they were favored by golf courses. Jacobsen is now owned by Textron and is based in England.
Specifications:
Engine: Two-Stroke Single, Port Induction
Cooling: Shrouded, Fan Cooled
Bore & Stroke: 2.00 Inches x 1.625 Inches
Displacement: 4.71 Cubic Inches
Carburetor: Tillotson MT8A
Drive: Belt / Jackshaft Clutch
Frame: Excelsior Schwinn
Wheels/Tires: 26 x 1.75 Inches
Wheelbase: 44 Inches
Phone: (319) 462-3925
E-mail: museum@nationalmcmuseum.org
Museum: 102 Chamber Drive Anamosa, IA 52205
Mailing: PO Box 405 Anamosa, IA 52205
