29er (bicycle) used were forks designed for trekking bikes or hybrids. For many years, 29" frames and bikes were usually only available from small little-known manufactures like Niner Bikes. Surly Bikes introduced their 29" frameset, the Karate Monkey, in 2002. Gary Fisher Bicycles, a division of Trek Bicycles, became the first of the major manufactures to offer a line of 29" bikes. Their lines never sold well until the introduction of single-speed 29" bike the Rig, in 2004. Today, most bicycle manufacturers in the US market offer at least one 29" bicycle or frame. Even companies that openly dismissed 29" as a
Tandem bicycle very same reason. Some argue that this produces a smoother power stroke, or that it reduces stress on the drive train because the point of maximum power is reduced to roughly half and distributed over the chainrings. Since the market for tandem bicycles is significantly smaller than the market for single bikes, there are far fewer tandem bicycle manufacturers than single-bicycle manufacturers. There are a few builders who specialize in tandems, as well as single-bike makers who offer tandem models. Current notable tandem bicycle manufacturers include: Tandem bicycle The tandem bicycle or twin is a form of bicycle (occasionally a