Mountain Bike



A mountain bike, mountain bicycle or ATB (All Terrain Bicycle) is a bicycle designed for off-road riding, either on dirt trails or other unpaved environments; in contrast, road bicycles aren't rugged enough for such terrain.

Mountain bikes have fat, knobbly tires for extra traction. In recent years front suspension has become the norm and full front and rear suspension suspension is becoming increasingly common. Some mountain bikes are also fitted with bar ends on the handlebars, but with a recent trend in riser handlebars (as opposed to a flat straight handlebar) fewer riders use bar end extensions. The bikes normally have 26 in (660 mm) wheels although since 2002, some models have been available with 29 in (737 mm) wheels. The larger wheels supposedly roll better over obstacles but this comes at the expense of less manoeuvrability and significant uptake is stymied by the limited selection of tyres and forks on offer.

There are newer Mountain bikes with either 24 or 27 speed derailleur gears. In French a mountain bike is called a VTT (vélo tout-terrain: "all-terrain bicycle").

Designs

Freeriding on a Hardtail freeride bicycleMountain bikes can be classified into three categories based on suspension: Rigid - no suspension Hardtail - front suspension fork, no rear suspension Dual or Full suspension - front suspension fork and rear suspension integrated into the frame Designs vary to reflect the challenges of the different disciplines in mountain biking:

Cross Country (XC) Mountain Bikes tend to have only a small amount of suspension (usually 80-100 mm) on the front and rear, and weigh comparatively little. This is achieved through the use of lightweight materials and suspension is typically provided by metal coil or air shocks. XC bikes can weigh as little as 20 pounds (9 kg), up to around 30 pounds (14 kg).

Enduro (or "All-Mountain") Bikes are generally heavier than XC bikes at between 30 and 35 pounds (14 to 16 kg), and have more suspension travel, between 100 and 150 mm of front and rear travel. They are designed to be able to ascend and descend the mountains, integrating some of the lightweight climbing attributes of cross-country bikes and the strengths of downhill/freeride bikes.

Freeride Mountain Bikes are a step up again from Enduro bikes. They tend to have the same 8 in (200 mm) of suspension travel of downhill bikes, and are built from stronger, heavier materials. They are designed to be an all-rounder, able to cross distances (although not as quickly or efficiently as an XC bike) and able to take on dangerous and technical downhill trails (though not as quickly or effectively as a specialist downhill bike). Many freeride bikes more closely resemble downhill bikes and weigh as much, though they are usually designed to be easier to pedal than a downhill bike. Freeride bikes range in weight from the low 30 to upper 50 pounds.

Downhill Mountain Bikes tend to be very heavy at over 40-50 pounds (18 to 23 kg) and have 8 in (200 mm) or more suspension travel. They are very strong and (because of typically large, high gears and long, soft travel) are suitable only for riding down dedicated downhill trails and race courses.

Trials Mountain Bikes that are set up very specifically for the purpose of bicycle trials. They typically have no suspension at all and only one gear, making them functionally more like an oversized BMX bike than a conventional mountain bike. Some trials bikes have no seat at all, or a vestigial pad, as the rider spends all of his time out of the saddle. These bikes are significantly lighter than almost all other mountain bikes, ranging from 15 to 25 pounds. This makes maneuvering the bike much easier.

Dirt Jumping, Urban and Street Mountain Bikes lie somewhere in between a trials bike, a BMX bike and a freeride bike. They are typically very strong bikes, with 3 to 5 in (75 to 125 mm) of front suspension, no rear suspension, and often with just one gear.

Singlespeeds Singlespeeding is as much a life style as it is a type of mountain bike. A singlespeed is just what it sounds like - a mountain bike with one gear. Most singlespeed riders choose to ride such bikes out of a love of simplicity, elegance, and passion. The gearing ratio depends totally on the terrain being ridden, the strength and skill of the rider, and the size of the bike (a 29er often requires a different gearing than a standard 26er). Often singlespeeds are fully rigid, steel-framed bikes. One of the more popular makers of singlespeeds is Surly. 4X racing is a new format, and there are curently bikes emerging to fit into that scene. these bikes are either full suspension with 3 to 4 inches of travel, or hardtails, and usually have quite strong frames. They run a chainguide on front and gears on the back.