Bicycle suspension

Bicycle suspension is the system, or systems, used to suspend the rider and bicycle in order to insulate them from the roughness of the terrain. Bicycle suspension is used primarily on mountain bikes, but is also common on hybrid bicycles.

Bicycle suspension can be implemented in a variety of ways, and any combination thereof:

Bicycles with only front suspension are referred to as hardtail and bicycles with suspension in both the front and rear are referred to as dual or full suspension bikes. When a bicycle has no suspension it is called rigid. Bicycles with only rear suspension are uncommon although the Brompton folding bicycle is equipped with rear only suspension.

Although a stiffer frame is usually preferable, no material is infinitely stiff and therefore any frame will exhibit some flexing. Bicycle designers intentionally make frames in such a way that the frame itself can absorb some vibrations.

Besides providing comfort to the rider, suspension systems improve traction and safety by helping to keep one or both wheels in contact with the ground.

As early as 1885, the Whippet brand of safety bicycle was notable for its use of springs to suspend the frame.

Front suspension is often implemented using a telescopic fork. The specifics of the suspension depend on the type of mountain biking the fork is designed for and is generally categorized by the amount of travel. For instance, manufacturers produce different forks for cross-country (XC), downhill (DH), freeride (FR) and enduro (ND) riding which all have different demands for amount of travel, weight, durability, structural strength and handling characteristics.

Suspension fork design has advanced in recent years with suspension forks becoming increasingly sophisticated. The amount of travel available has typically increased. When suspension forks were introduced, 80–100 mm of travel was deemed sufficient for a downhill mountain bike. This amount of travel is now common for cross-country disciplines, whereas downhill forks typically offer 200 mm of travel for handling the most extreme terrain.

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