Single-speed bicycle on the situation, a messenger may prefer a mountain bike based single-speed, which can roll over many obstacles, or a fast and light road bike-based single-speed. In the United States market, bicycle companies such as Bianchi, Cannondale, Fuji Bike, KHS, Kona, Raleigh, Giant, Specialized, Swobo, Felt, Trek and Niner all have produced and marketed single speed bicycles. Because most full suspension frame designs either have a single pivot that is not concentric with the bottom bracket, or a linkage with a variable center of rotation, the distance between the bottom bracket and rear axle varies throughout the suspension's travel. This
Trek Bicycle Corporation in the company. Despite the split, Trek and Trek Travel enjoy a close working relationship. In 2003, Trek acquired Villiger, a Swiss bicycle company, and Diamant, the oldest bicycle company in Germany. The acquisition gave Trek a foothold in the active-leisure bicycle market, an important segment in Europe. As part of the acquisition, Trek took over ownership of the Villiger-Diamant production facility in Hartmannsdorf, Germany. Trek's global expansion continued in 2005, when Trek expanded into the Chinese market by opening two stores in Beijing and signing deals with 20 Chinese distributors. For the third time in its history, in 2005