The Bigha bicycle (541.738.4340, www.bigha.com) might be a common sight in Corvallis, Ore., hometown of the company that builds the $3,000 machines, but during a test ride along the shore of Boston’s Charles River, everyone stops to stare at it. It might be the bike’s blinking directionals, or flashing brake lights that command attention. More likely, however, it is the position of the rider. Aboard the Bigha, you lean back against the adjustable padded seat with your feet placed forward on the pedals and your hands on the chopper-style handlebars, reducing fatigue, neck strain, and posterior discomfort associated with traditional bikes. The 47-pound Bigha is challenging to operate when you are traveling slowly or negotiating an incline. But at speed on paved and other flat surfaces, the 27-speed bike rides superbly.