Also called:
U.S. Route 66 or U.S. Highway 66

News

Route 66, one of the first national highways for motor vehicles in the United States and one that became an icon in American popular culture.

Background and construction

The system of major interstate routes—12 odd-numbered ones, running generally north-south, and 10 even-numbered ones, running generally east-west—was laid out in a proposal created by the American Association of State Highway Officials and accepted by the U.S. secretary of agriculture in November 1925. The route from Chicago to Los Angeles was designated U.S. Highway 60. Various states raised objections to this designation. For example, Kentucky protested that the plan left that state out entirely and that, based on the placement of the other proposed east-west roads, a highway numbered 60 logically should run through Kentucky. Kentucky subsequently received the route number 60, and the original Route 60 was changed first to 62 and then to 66 in the final version of the plan, approved on November 11, 1926.

The original eastern terminus of the route in Chicago was at the intersection of Michigan Avenue and Jackson Boulevard; a few years later it was moved some blocks east to U.S. Route 41, better known as Lake Shore Drive. The western terminus in Los Angeles was originally at Broadway and 7th Street; later it was moved westward to U.S. Route 101 ALT (now Lincoln Boulevard at Olympic Boulevard) in Santa Monica, California.

Among the other cities served by the route were, from east to west, Springfield, Illinois; St. Louis, Springfield, and Joplin in Missouri; Tulsa and Oklahoma City in Oklahoma; Amarillo, Texas; Tucumcari, Santa Fe (later bypassed), Albuquerque, and Gallup in New Mexico; Holbrook, Flagstaff, and Kingman in Arizona; and Needles, Barstow, and San Bernardino in California.

While the system of numbered routes was a federal creation, the actual construction of roads to carry those routes was left to the individual states. Laid in part over preexisting auto trails, Route 66 was thus built in segments, often discontinuous ones, and was not entirely paved until 1938. The original route was officially commissioned to stretch a total of 2,448 miles (3,940 km), but, once built, it fell short of that figure. Over the years a number of projects relocated sections of the route, usually with the effect of further shortening it. Only the segment passing through Kansas, all of 13 miles (21 km) in length, remained unaltered. The elimination of a diversion through Santa Fe in 1937 cut more than 100 miles (160 km) from the route. These projects reflected a deeper change in the perceived purpose of the national highways: originally a means of promoting commerce along their lengths, they came to serve as the essential elements in increasingly popular long-distance automobile travel. To the same end, Route 66 was rerouted around most larger towns and cities in order to avoid slower local traffic.

Rise and demise of the route

By the mid-1930s, Route 66 was already being called the “Main Street of America.” Early promoters, notably John Woodruff of Springfield, Missouri, and Cyrus Avery of Tulsa, had envisioned a great road linking towns across the continent, and the organizations they founded to advance the idea were in effect multistate chambers of commerce. True to the promoters’ foresight, traffic on the highway increased, a growing share of it long-distance, and the need for food, fuel, repairs, and shelter transformed the economies of the towns through which the route passed. The development of novel methods of merchandising to the transient customer that became commonplace in mid-20th-century America—drive-in and drive-up businesses, fast food, motor inns, and roadside advertising—can to a great degree be traced to the influence of Route 66 in those towns. The large-scale migration to California of the “Okies,” dispossessed rural people from the Dust Bowl states during the 1930s, accelerated that development and also produced yet another byname for the highway, the “Mother Road,” so called in John Steinbeck’s novel of that migration, The Grapes of Wrath (1939).

The explosion of automobile traffic that followed the end of World War II provided the perfect milieu for a song memorializing the journey “from Chicago to LA, more than two thousand miles all the way.” Written by Bobby Troup and recorded by Nat King Cole in 1946 and by many other artists in subsequent years, “Route 66” invited the listener to “get your kicks” on that very road. From 1960 to 1964 a television series of the same name featured two adventurers who cruised the highway in a Chevrolet Corvette sports car. At the same time, the rapid expansion in traffic meant that Route 66, even more than many other interstate routes, was carrying far more vehicles than it was designed to bear.

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More and heavier traffic, more stringent safety requirements, and improved construction methods created a demand for a new kind of federal highway system. By the time U.S. Pres. Dwight D. Eisenhower signed the Federal-Aid Highway Act of 1956, a few segments of Route 66 had already been superseded by newer, wider, and safer roads. The act authorized federal funding for an Interstate Highway System of such roads, and, despite an appeal by the state of Missouri on behalf of all the Route 66 states, there was to be no Interstate 66. Route 66 gradually was replaced by portions of several of the new high-speed limited-access superhighways. In many places these highways paralleled the old route or were built over its right-of-way. By 1977 the route had ceased to exist in Illinois, and in October 1984 the last segment was bypassed in Arizona. Route 66 was formally decommissioned on June 27, 1985.

Many private individuals, organizations, and towns have preserved portions of the roadway, businesses that throve on it, or collections of memorabilia. Among several museums dedicated to the route are those in Clinton, Oklahoma, and Barstow, California.

Robert McHenry
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Gottlieb Daimler
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vehicle

motorcycle, any two-wheeled or, less commonly, three-wheeled motor vehicle, usually propelled by an internal-combustion engine.

History

Just as the automobile was the answer to the 19th-century dream of self-propelling the horse-drawn carriage, the invention of the motorcycle created the self-propelled bicycle. The first commercial design was a three-wheeler built by Edward Butler in Great Britain in 1884. It employed a horizontal single-cylinder gasoline engine mounted between two steerable front wheels and connected by a drive chain to the rear wheel.

By 1900 many manufacturers were converting bicycles—or pedal cycles, as they were sometimes called—by adding small, centrally mounted spark ignition engines. The need for reliable constructions led to road motorcycle trial tests and competition between manufacturers. The original Tourist Trophy motorcycle races were held on the Isle of Man in 1907 as reliability or endurance races. Such events have been the proving ground for many new ideas from early two-stroke-cycle designs to supercharged, multivalve engines mounted on aerodynamic, carbon-fibre reinforced bodywork.

Components

Motorcycles are produced with both two-stroke- and four-stroke-cycle engines and with up to four cylinders. Most are air-cooled, though a few are water-cooled. Engines are generally limited to displacements of about 1,800 cc. The smallest designs, termed mopeds (from “motor pedal”), have very small engines (50 cc) with fuel economies of as much as 2.4 litres per 100 km (100 miles per gallon). Such units are not permitted on limited-access public roads because of their low speed capability. In order of increasing power capacity and engine displacements, the other five classifications are child bikes, trail bikes, road bikes, touring bikes, and racing bikes. A subcategory of racing bikes is known as superbikes. These are motorcycles that displace more than 900 cc and in which the seat is tilted forward so that the rider is hunched over the frame, creating a more aerodynamic profile.

The motorcycle frame is often of steel, usually a combination of tubes and sheets. The wheels are generally aluminum or steel rims with spokes, although some cast wheels are used. Graphite, composite, and magnesium parts are increasingly in use because of their high strength-to-weight characteristics. Tires are similar to those used on automobiles but are smaller and rounded to permit leaning to lower the centre of gravity in a turn without losing traction. The gyroscopic effect of motorcycle wheels rotating at high speed significantly improves stability and cornering ability. Inertia and steering geometry are also significant factors. Front-wheel suspension is provided by coil springs on a telescopic fork; rear-wheel springs are often mounted on shock absorbers similar to those used in automobiles.

Transmissions on motorcycles typically have four to six speeds, although small bikes may have as few as two. Power is normally transmitted to the rear-wheel sprockets by a chain, though occasionally belts or shafts are used.

The clutch and throttle, which control engine speed, are operated by twist-type controls on the handgrips. The front-wheel brake is controlled by a lever near the handgrip; the rear-wheel brake is engaged by a foot pedal. Except on very small machines, the front brake is usually of the hydraulic disc type. The rear brake may be disc or drum. The kick starter has been mostly replaced by an electric push-button starter.

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Emissions standards

Tailpipe emissions standards for motorcycles continue to be strengthened. In 1980 the U.S. Environmental Protection Agency (EPA) first regulated new motorcycle hydrocarbon emissions, requiring motorcycles to emit less than 5.0 grams per km (0.3 ounce per mile) of highway driving. California and the European Union (EU) imposed stricter limits on hydrocarbons and added restrictions on nitric oxides and carbon monoxide. In 2006 emissions from new motorcycles sold in the United States were limited to a combined 1.4 grams of hydrocarbons and nitric oxides and 12.0 grams of carbon monoxide per km. The EPA decreased the limit on combined emissions of hydrocarbons and nitric oxides to 0.8 gram in 2010. The EU reduced emissions from new motorcycles in 2004 to 1.0 gram of hydrocarbons, 0.3 gram of nitric oxides, and 5.5 grams of carbon monoxide per km; in 2007 these levels were further reduced to 0.3 gram of hydrocarbons, 0.15 gram of nitric oxides, and 2.0 grams of carbon monoxide per km. The EU did a further emission reduction in 2016 to 0.17 gram of hydrocarbons, 0.09 gram of nitric oxides, and 1.14 grams of carbon monoxide, with a further reduction to 0.1 gram of hydrocarbons, 0.06 gram of nitric oxides, and 1 gram of carbon monoxide planned for 2020. Although U.S. limits for carbon monoxide were not lowered by law, the required reductions in other pollutants effectively lowered carbon monoxide emissions in fact. In order to meet these “clean-air regulations,” manufacturers installed more sophisticated catalytic converters and fuel-injection systems.

George C. Cromer