The world's first ATV, Honda's three-wheel US90, was introduced to America in 1969. The US90, later renamed the All-Terrain Cycle 90 (ATC) in 1971, was powered by an 89cc four-stroke single-cylinder engine that sent its 7-horsepower through a dual-range four-speed gearbox with automatic clutch. It featured extras such as a Swivel-Lok handlebar for easy loading in a trunk or station wagon, and was sold for just $595.  
Honda engineer Osamu Takeuchi headed the US90 development program, which began in 1967, when American Honda asked Honda R&D for a new product that dealers could sell when motorcycle sales tapered off in the winter.  Takeuchi began with a head full of ideas and an eclectic assortment of components. Two-, three-, four-, five- and even six-wheeled configurations were examined, but the three-wheel concept was the best configuration for the machine's intended mission. It dealt with snow, mud and assorted slippery conditions a two-wheeler couldn't, while providing more maneuverability than other proposed designs.  In the early stages, a Honda ST70 motorcycle gave up its 70cc four-stroke single-cylinder engine for the cause, along with assorted chassis parts. Two-drive wheels in the rear worked well, but the biggest challenge was finding tires capable of getting a grip on soft terrain such as snow, sand and mud. Motorcycle tires weren't an option.  The design process quickened when American Honda sent Takeuchi an American invention called the Amphi-Cat® that rolled on six, 20-inch, low-pressure, high-flotation balloon tires. Revamping the ST70-based prototype to accept the new low-pressure rolling stock, engineers went to work on a new tire design, ending up with a low-pressure, 22-inch tire. With the tire dilemma solved, the engine became the focus. The powerplant wasn't powerful enough, so displacement was bumped to 90cc, and a special dual-range four-speed gearbox with automatic clutch added flexibility over varied terrain. Rough terrain makes suspension an integral part of the modern ATV; but, 30 years ago, Takeuchi's original balloon tires did the job alone. Because of their large footprint and low operating pressures, ATV tires exerted less pressure on soft or sensitive terrain than the average human foot. Those tires let the vehicle go places others couldn't, leaving little or no damage in their passing, an advantage that remains a cornerstone in hundreds of modern ATV applications.  Though it was primarily a recreational vehicle through the '70s, commerce, more than sport, shaped the ATV's future, as everything from agriculture to industry to construction found new and innovative uses for these versatile vehicles. Honda engineers followed their machines into the field, gathering data to guide the machine's natural adaptation to a rapidly growing and amazingly diverse market.  Since Honda's original US90 debuted 30 years ago, ATVs have topped 6.5 million in sales worldwide, and millions of recreational riders, farmers, ranchers, commercial business owners, search and rescue teams and forest service people wonder how they ever got along without their ATVs. And it all began with the Honda US90.