Amerikaanse motoren

Iver Johnson (1893-1916)

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Launched in Fitchburg, MA in 1907, The Iver Johnson Company motorcycle division was born from the conversion of a line of business that had been manufacturing bicycles for some 23 years prior to that point. Ultimately, the arms division of the business was growing so rapidly to meet demand that management decided to focus on that market and as a result motorcycle operations closed in 1916 (varying sources claim the last year as being 1915, with 1916 seeing only the sales of remaining 1915 produced inventory), bringing to an end 33 years of total cycle operations (23 for bicycles, and another 10 for motorcycle and run-off bicycle business).

In The Illustrated Directory of World Motorcycles, author Mirco de Cet reports:

Iver Johnson's Arms and Cycle Works had been building bicycles for 23 years when it entered the motorcycle business, and had started manufacturing firearms many years earlier. The Iver Johnson design was unconventional in many respects. The top and middle frame tubes were bent to arch over the engine, and the front fork was an interesting leading link, leaf spring design. Customers could choose either rigid or swingarm rear suspension. This was known as a keystone frame, one that employs the engine as a stressed member.

The side-valve singles and twins had two different valve mechanisms. The belt-drive single featured a longitudinal camshaft driven by worm gears, the saft extending forward through the case to drive the magneto. On the V-twin and chain-drive single, the cams were incorporated in a large ring gear driven by a pinion gear on the crankshaft. The magneto on these engines was chain-driven. The V-twin was designed with offset crankpins, which provided evenly spaced combustion strokes, so exhaust note sounded like a vertical twin. The engine featured both mechanical and hand oild pumps. Final version of the twin were equipped with a planetary clutch, with either an Eclipse two-speed hub or a single speed. The twin was rated at eight horsepower, and the single at 4.5 hp.

In 1916 the market for weapons began to seriously outstrip the prospects for motorcycle sales, so the company turned its attention to firearms and tools.

As de Cet notes, there were options and variations of models of I-J motorcycles available, such as belt drive vs. chain drive, or solid-rear vs. suspended swingarm, but mostly they were categorized by engine type, either V-Twin or Single Cylinder configurations, with other characteristics being considered as "Options," and not necessarily defining traits of a particular model. The specifications for the basic model classifications are:

(V-Twin) Engine: Side-valve V-twin (Transversely Mounted, with one cylinder pointing forward, and the other backwards, with an acute angle between them Fuel: Gasoline (leaded) Displacement: 1020 cc (62.22 in³) Power: 7 to 8 hp (5 to 6 kW) Wheelbase: 58in (147 cm) Weight: 265 lb (120 kg) Top speed: 65 mph (105 km/h) Starting: Pedal Drive: Belt or chain

(Single) Engine: Single cylinder (Vertically Mounted) Fuel: Gasoline (leaded) Displacement: 500 cc (30.512 in³) Power: Unknown Wheelbase: Unknown Weight: Unknown Top speed: Unknown Starting: Pedal Drive: Belt

According to Jeffry L'H. Tank's History of the Motorcycle, Iver Johnson advertised their machines as "Mechanical Perfection," a boast that was that not entirely unbelievable given the number of advanced design features in especially their later models, such as dual crankshafts, nickel-alloy machined parts, chain drive, and a hand-operated three-speed gearbox. In fact, amongst collectors and researchers such as Tank who have the benefit of hindsight, Iver-Johnsons of the day, such as the 1915 Model 15-7 are the finest period examples of motorcycle engineering of the day, along with a very select few others, such as Scotts.

In modern times, Iver Johnson motorcycles are as rare and collectible as any of the products of the myriad other early short-lived American motorcycle manufacturers that existed during the early days of the technology, such as Holley or Henderson, or even from British/European manufacturers like The Scott Motorcycle Company or Brough Motorcycles or Daimler-Maybach or Hildebrand and Wolfmuller. Considering that production ran for only 10 years, with 2 of those being used for the startup and shutdown of operations, examples of Iver Johnson motorcycles at all are rare, let alone those in collectible condition, and collectors should expect to face considerable difficulty in finding them and great expense when they are ultimately found (especially if found in restored, authentic condition).

Though all vestiges of Iver Johnson as a going concern are now gone as of 1993, there is still a great deal of interest in the company and the collection of their products, although that interest is focused on their firearms business and not their motorcycle business. Where their motorcycles are collected, they are collected as examples of early motorcycles (as is the case with the products of many of the companies from the early days of the industry) and in an effort to catalog all of the early manfacturers, not so much out of inherent interest in Iver-Johnson motorcycles themselves.

De Cet's book features a few nice images of restored, collectors' Iver Johnson motorcycles

Iver Johnson
1914 - Iver Johnson

Iver Johnson
1914 - Iver Johnson

Iver Johnson

Iver Johnson

Iver Johnson
1897 - Iver Johnson
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