Unrestored 1907 Strap Tank Single is a True Survivor

Picture Perfect

Mecum Auctions dubbed this 1907 ‘Strap Tank’ Model 2 the “Mona Lisa of Harley-Davidsons.” A true survivor from the E.J. Cole Collection, this patinaed work of art is considered to be the best unrestored Strap Tank in the world. In 2015, it fetched a record $650,000 at auction, making it one of the most valuable Harley-Davidson motorcycles sold to date.

All photos courtesy of Mecum Auctions

Add It Up

The 'Mona Lisa' Strap Tank is also a rare machine. With an engine serial number reading 2037, it is considered to be the thirty-seventh machine, out of 150 built in 1907, making it the ninety-fourth motorcycle ever built by the Motor Company. To put the numbers in perspective, Harley-Davidson built around 50 machines in 1906, and had tripled their production to 450 machines by 1908.

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Namesake

The Strap Tank gets its name from the nickel-plated steel bands that secure the fuel and oil tanks to the frame. By 1909, the tank was redesigned and the straps were no longer used. Unlike restored examples, Strap Tank #2037 has a finish that has been decades in the making. The 'ran when parked' appearance of the motorcycle only adds to its authentic value.

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Jumpy Moniker

Harley-Davidsons of the era were also known as 'The Silent Gray Fellows.' The nickname, and possibly the Motor Company's first brand-slogan, was due to their effective mufflers. A far cry from today's decibel challenging exhausts, the Strap Tank was a desirable motorcycle because it did not startle horses — still the backbone of industry and transport at the time.

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Robust Competition

The Harley-Davidson Motor Company officially incorporated in 1907. The year before a new factory had been built on Chestnut Street, later renamed Juneau Avenue, in Milwaukee, Wisconsin — now the location of the corporate headquarters. With a staggering 150 other American motorcycle companies in operation, the competition was steep in the early 1900s. Yet, Harley-Davidson earned a reputation for building a robust and reliable motorcycle, which led to an order by the Detroit Police Department.

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Pedal Power

By 1907, the Strap Tank's atmospheric valve engine was an already obsolete configuration. At 26.84 cubic-inch, or 440cc, the single put out a healthy four horsepower. The air-cooled engine was lubricated by a total-loss oiling system. The Strap Tank engine and loop-frame design took it out of the motorized bicycle category, known as 'power-cycles,' and marked the path of future Harley-Davidson motorcycle designs.

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Chain Throttle

The right-hand twist throttle assembly was connected to the Schebler carburetor via a pulley and chain, and mechanical linkage. The rear lever on the tank operated a cut-out baffle in the muffler. Starting the Strap Tank was a combination of opening the fuel valves to fill the carburetor, and setting the drip rate of the oil.

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Connected Crank

The forward lever was connected to the timing mechanism on the right crankcase. Pulling the timing lever back to full retard also opened the exhaust baffle — a rudimentary form of compression release. The total-loss battery is attached by a wire above the timing mechanism. To the left of the timing mechanism is the oil line that dripped directly onto the crank.

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Direct Drive

The engine drove the rear wheel directly via a large leather belt, without a clutch or transmission. A lever on the left of the fuel tank served as a rudimentary 'clutch' and engaged the belt tension through a sprung idler pulley. Starting the Tank Strap on its rear prop stand was a fairly straight-forward process if the correct procedure was followed.

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Pedal Start

With the fuel and oil valves flowing, the timing retarded, and tension on the belt, the pedals were used to turn the engine over. Once at speed, the timing lever was advanced and the engine would start. The 185-pound Strap Tank was capable of 40 mph. Considering the bicycle tires, rear coaster brake, and the limitations of early twentieth-century roads, top speed must have been an exhilarating ride.

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Sprung Vision

A sprung saddle seat absorbed the road bumps, while a set of strengthened Sager Cushion Forks dampened shocks out front. The Strap Tank may be a relic of yesterday, but #2037 carries with it a sense of passion and dedication to craft — which sounds very similar to the prerequisite for a work of art.

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