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For many people living in the United States, the bicycle is considered a recreational vehicle, or perhaps an occasional mode of personal transportation. Those in developing or Third World nations around the globe, however, see the bicycle as an indispensable tool not only for getting around, but also for carrying cargo. Tucson, Arizona native Ross Evans noted this as he traveled in Central America while pursuing degrees in Mechanical Engineering and Latin American Studies at Stanford University. His interests in this pair of subjects lead him to ponder the problem of how to improve the bicycle’s ability to carry heavy loads. He realized the devices’ usefulness was limited in many situations, despite their benefits of being an inexpensive, efficient, and environmentally safe and clean means of transport.


In 1995, at the age of 20, Evans began working on a solution to this problem. He was awarded several research grants, which allowed him to go to Nicaragua and teach people there to repair and build cargo bikes. He began talking with workers, commuters, farmers and engineers about their needs. In the bike shop Evans set up in Nicaragua, he developed the idea for the Xtracycle.

The Xtracycle converts a regular bicycle into a vehicle that can carry substantial loads by increasing the distance between the pedals and the rear wheel. Adding a simple frame extension gives the rider a space just behind him where he can place his load. Additionally, a longer chain and brake cable must be attached. With these relatively easy-to-manufacture, inexpensive adjustments, a rider can carry a load up to 200 pounds on his bicycle. The Xtracycle can empower those with no access to cars or those who are not physically able to carry an awkward bundle of cargo.

Evans returned to the United States and refined his design while working at the Lemelson Center for Invention, Innovation, and Creativity at Hampshire College. He returned to Stanford and secured grants from the National Collegiate Inventors & Innovators Alliance to continue working on the Xtracycle and tested it in Cuba and Africa. To productionize the Xtracycle in foreign countries, he began a program of teaching locals to weld.

With his friend Kipchoge Spencer, Evans founded Xtracycle International. He graduated from Stanford and has since introduced the Xtracycle in communities around the world in nations such as Ghana, Senegal and South Africa. Xtracycle is focused on selling its kits in the U.S. to become profitable; eventually the company plans to expand initiatives that will bring the kits to developing countries. They have a basic version of the product they call the “Extrabike,” which they hope they can donate, rent, or sell at a very low price to people in need. The company is also very active in non-profit organizations such as the Xtracycle Access Foundation. Xtracycle operates out of Nevada City, California.

[June 2004]

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