A downhill bike (also known as a downhill mountain bike) is a full suspension bicycle designed for particularly steep, rocky trails. A mountain bike or mountain bicycle (abbreviated MTB or ATB (all terrain bicycle is a Bicycle designed for off-road cycling including Suspension is the term given to the system of springs, Shock absorbers and linkages that connects a Vehicle to its Wheels Suspension The bicycle, cycle, or bike is a pedal-driven, human-powered vehicle with two wheels attached to a frame, one behind Unlike a typical mountain bike, durability and stability are the most important design features, compared to lighter, more versatile cross-country bikes. Cross-country ( XC) cycling is the most common discipline of Mountain biking. Downhill bikes are primarily intended for high speed descent, and downhill riders will usually shuttle, via chairlifts or motorized vehicles, to the trailhead.
Downhill bikes are typically made of aluminum or steel, will have 7-12 inches (180-300mm) of rear suspension travel, and be designed around a 7-8 inch (180-203mm) suspension fork. The suspension sag is also much higher than cross-country bikes (25%-50% of total travel vs. 10%-20%) for a more supple ride at higher speeds.
These bikes will also have very slack head tube angles (66 degrees or less), extremely long wheelbases (over 45 inches), and will accommodate the use of 3 inch width knobbed tires. Downhill frames are also overbuilt to handle the stress of riding over rocky terrain, drops, and jumps. A bicycle frame is the main component of a Bicycle, onto which wheels and other components are fitted Dirt jumping is one of the names given to the practice of riding bikes over cement type jumps of dirt or soil and becoming airborne Bike weights have been typically over 40lbs (18kg), but modern downhill bikes have broken the 45lb weight barrier (such as the Trek Session 10, weighing in at almost 50lbs). Some newer (2007/8) downhill bikes can be built to weigh under 35lbs, such as the Santa Cruz V10 or the GT DHi.
Other features include 8 inch (203mm) disc brakes and a chain guide to prevent accidental chain deraillment. The disc brake or disk brake is a device for slowing or stopping the rotation of a Wheel. Other innovations include the use of OnePointFive headtube standard, which uses a 1. 5" wide headtube (see headset), instead of the more conventional 1. The headset is the set of components on a Bicycle which provide a rotatable interface between the Bicycle fork and the Bicycle frame itself 125" diameter, for added stiffness and strength. Adjustable headtube angles are also available to adapt the bike to the owner's preferred style of riding.
There has been a recent trend in downhill for lighter, shorter, better modulated suspension travel in bikes, such as the new Sunn downhill bike, which only has 7 inch rear wheel travel, compared to most modern downhill bikes with 10-12 inch rear wheel travel.
Manufacturers
- Brodie
- Cannondale
- Giant
- Iron Horse
- Kona
- Norco
- Rocky Mountain
- Santa Cruz
- Specialized
- Lapierre
- Tomac
External links
IMBA (International Mountain Biking Association) "A Brief History of the Mountain Bike" by Jobst Brandt Mountain Bike Roots - photos and race results from 1980's events MTBrider - Northern Ireland's mountain bike community
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The Cannondale Bicycle Corporation is a major American Bicycle manufacturer headquartered in Bethel Connecticut USA with manufacturing in Bedford Giant Manufacturing Co Ltd is a Taiwanese Bicycle manufacturer and the world's largest bicycle manufacturer Iron Horse Bicycles is a manufacturer of Bicycles based in Islandia New York, United States Rocky Mountain is a Canadian Manufacturer of mountain bikes. Their first model was developed in 1978 by two British Columbians that put wide Lapierre or LaPierre is a surname and may refer to Dominique Lapierre - French author Edmond Lapierre (1866–1960 - CanadianDapyx Software network: MP3 Explorer | Ebook Manager | Zenithic