Mountain biking
Mountain biking is cycling on unpaved trails and rough terrain with bicycles built to handle obstacles, steep gradients, and uneven surfaces.
Mountain bike suspension: A bicycle system that lets wheels move relative to the frame to absorb impacts and maintain tire contact. Suspension reduces the force of trail impacts and helps tires stay planted on rough descents.
Cross-country mountain biking: A mountain biking discipline centered on riding varied courses that combine climbing, descending, and technical terrain. It emphasizes efficient climbing and sustained effort as well as bike handling.
Singletrack: A narrow trail roughly wide enough for one bicycle, commonly winding through natural terrain. Singletrack is a defining trail setting, with limited room for passing and line changes.
Repack race: A downhill bicycle race held on Mount Tamalpais in California during the 1970s, named for riders repacking overheated coaster brakes. These early races helped establish off-road bicycle competition in the area where the sport took shape.
Road cycling: Cycling primarily on paved roads, using bicycles designed for efficient travel on smooth surfaces. Road cycling shares the bicycle but contrasts with mountain biking's rough surfaces and obstacle-focused handling.
Mountain bike geometry: The dimensions and angles of a mountain bike frame that shape handling, stability, and rider position. Frame geometry affects climbing, cornering, and stability on steep, uneven trails.
Downhill mountain biking: A mountain biking discipline in which riders descend steep, technical courses against the clock. Its courses prioritize descending speed, line choice, and impact control.
Mountain bike trail: A path designed or maintained for mountain biking, ranging from natural routes to engineered features. Trail surfaces, gradients, and obstacles shape the demands placed on riders and bikes.
Marin County: A county north of San Francisco whose Mount Tamalpais trails were central to early mountain biking. Its riders, trails, and informal races formed a major center of the sport's early development.
Cyclocross: A bicycle racing discipline on short circuits that combine pavement, dirt, barriers, and occasional running with the bike. Cyclocross uses off-road sections but differs in course format, obstacles, and typical bicycle design.