Minibike History
Article by Mark Trotta
Although first seen in the 1940s, it wasn't until the go-kart craze of the 1960s that brought the mini-bike back into vogue. As with karts, the list of manufacturers grew quickly, including brands such as Rupp, Rutland, Fox, Lil Indian, Cat, Arctic Cat, Taco, Heath, Gilson, and many others.
Minibike vs Scooter
Gas-powered scooters usually have an open-frame 'step-in' design, and have a taller seat height than minibikes. Quite often, they were equipped with lighting, which allowed them to be registered for road-use.
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Vintage American Scooters
Step-through gas scooters have been around since the 1890's. The Autoped, produced from 1915 to 1922, is often cited as the first U.S. mass-produced motorized scooter.
Picture Courtesy Smithsonian Museum
The Autped had no seat - the driver stood on a step-through platform.
The popularity of motor scooters in the U.S. continued growing in the 1930's. Much of this was from the advent of newly-built military bases, looking for a better way to relay communications.
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Cushman Scooters
From 1936 through 1965, Cushman Motor Works produced many styles and sizes of motor scooters. They were powered by several different kinds of engines through those years, but most commonly a five-horsepower single-cylinder four-stroke.
Cushman models include the Cub, Husky, Super Husky, Eagle, Silver Eagle and the Super Eagle. For several years, Sears-Roebuck sold their own version of a Cushman scooter under the Allstate brand.
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Doodle Bug
Marketed under the 'Hiawatha' brand name, the original Doodle Bug scooter was produced by Beam Manufacturing Company from 1946 to 1948.
Factory archives shows that a total of 40,000 original Doodle Bugs were built.
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Harley-Davidson Topper
Harley-Davidson produced the Topper scooter from 1961-1965. The front body, front fender and floorboards were steel, and the engine cover and body was fiberglass. Powering the Topper was a 165cc single-cylinder two-stroke engine mounted horizontally between the floorboards.
Chances of finding a Harley Topper project scooter today are not very good. It’s estimated that fewer than 3,000 were built.
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Early Minibikes
Starting in the 1950s, home-built minibikes began to appear, often powered by an old lawn mower engine and mounted to a tubed frame with no suspension.
One of the earliest companies was Li'l Indian, whose models featured a tubular frame with 4-inch wheels and 3- to 5-horsepower engine.
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Factory Minibikes
Seeing the popularity of mini-bikes soar, motorcycle manufacturers were quick to jump on the bandwagon. Honda, Kawasaki, Suzuki, Yamaha, and others all marketed a minibike, as did Harley-Davidson for several years. Today, factory minibikes from the 1960s and 1970s are very collectible.
The Honda Z50A was first available to American riders in 1968, with a model designated 'Z50'. An upgraded Z50AK3 with rear suspension was introduced in 1972.
All Z50 models are powered by a 50cc overhead cam four-stroke engine. Due to their riding position, they are often referred to as 'Monkey Bikes'.
Honda CT70
One of the most sought after factory minibikes today is the Honda CT70. Produced from 1969 through 1994, the CT70 featured a 72cc four-stroke engine with single overhead cam, folding handlebars, and a compact, monocoque chassis with it's fuel tank under the seat.
First year CT70's had no rear suspension, but Honda added a swing-arm and shock absorbers a few years later. Early models had two transmission choices, either a centrifugal clutch three-speed or a manual shift four-speed. After the four-speed was discontinued, only three-speed models were available, making the four-speed models more valuable.
Harley Shortster
The Harley-Davidson Shortster was available for 1972 only. Powered by a 65cc two-stroke engine, front suspension was telescopic (not oil dampened) with a swing-arm and twin shocks in the rear. Wheels were 10-inch, with a three-speed gearbox shifted by the rider's left foot. These Italian-made (Aermacchi) machines were offered in three colors: yellow, red, and blue.
Harley X-90
Replacing the Shortster in 1973 was the Harley-Davidson X-90 (also manufactured by Aermacchi). It was basically the same bike with a larger 90cc motor and four-speed gearbox. Harley offered the X-90 from 1973 to 1975.
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Collectability
Over the last few decades, vintage mini-bikes from the sixties and seventies have become sought-after by both collectors and enthusiasts. Today, desirable models in excellent condition exchange hands in the $2,000 - $3,000 range.
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