How Does
How Does a Suspension Fork Work on a Mountain Bike?
Basics
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Mountain bike suspension forks, or front shocks, are designed to absorb the impact that is common on rough mountain bike trails. They provide a more comfortable, stable ride over rough terrain that includes larger obstacles like rocks and logs. Forks utilize different construction, but all seek to activate when the front tire rolls over a bump. The main types of mountain bike forks are air and coil.
Compression and Rebound
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When the front tire rolls over a bump, the spring mechanism, whether it be air or metal coil, is activated and the shock compresses. Adjusting the preload of a fork alters how much pressure it will take to initiate compression. Add air or tighten the spring to make the fork more rigid. After compressing, the fork will rebound back into position. This compression rebound process absorbs the impact of trail obstacles, which would otherwise be felt in the cyclist's arms.
Damping
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When the fork compresses, a damping mechanism generates oil or air to control the movement of the fork so that it doesn't bottom out or bounce up and down repeatedly. The damping mechanism pushes oil or air between separate chambers through small holes and mitigates the speed at which the shock will compress and rebound. Most shocks include an adjustment for rebound damping, so that you can adjust how quickly the shock snaps back into place. Some forks also include a compression damping adjustment, which allows you to control the rate at which the shock compresses.
Other Features
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In addition to the basic aforementioned processes and features, some suspension forks include a number of other features and adjustments to make them more user-friendly. Forks use different amounts of travel, which is sometimes adjustable, to absorb different levels of impact. The biggest jumps and drops demand shocks with the most travel (8 to 10 inches). Many forks include a lockout knob, which allows the rider to make the fork completely rigid so that it doesn't suffer from unnecessary bounce during a climb.
eHow Article: How Does a Suspension Fork Work on a Mountain Bike?
