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 tools mechanism from rotating. Bicycle tools Various bicycle tools have evolved over the years into specialized tools for working on a bicycle. Modern bicycle shops will stock a large number of tools for working on different bicycle parts. This work can be performed by a trained bicycle mechanic, or for simple tasks, by the bicycle owner. Various devices have been devised to hold a bike still to facilitate working on it, and they are usually called stands. Stands may clamp a part of the bike, such as the seatpost, seat tube, or top tube, or they may simply provide a surface