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
Bicycle mechanic Bicycle mechanic A bicycle mechanic or bike mechanic is a mechanic who can perform a wide range of repairs on bicycles. Bicycle mechanics can be employed in various types of stores, ranging from large department stores to small local bike shops; cycling teams, or bicycle manufacturers. The New York State Department of Labor describes bicycle repair as a "realistic" occupation, meaning an occupation that would be enjoyed by somebody who likes "practical, hands-on problems," dealing with "real-world materials like wood, tools, and machinery," and one that "does not involve a lot of paperwork or working closely with others." They classify