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 American team riding an American made bicycle. Armstrong went on to win a record-setting seven-consecutive Tours de France, all of them aboard Trek bicycles. He did at some points ride a Litespeed bike, painted and badged as a Trek. In 2012, all of Armstrong's Tour victories were rescinded after Armstrong was found to have violated anti-doping regulations. In 1998, Trek established its Advanced Concepts Group (ACG), a collection of engineers and technicians dedicated to technologies development. The leading edge of Trek's design and engineering efforts, ACG is perhaps best known for a number of products introduced and used by Lance