A full suspension mountain bike glossary of terms:

To many mountain bikers, full suspension is full of questions. It’s unfortunate to just forget about it and go, but the reality is that many riders are missing out on the advantages of the suspension they paid for when they bought their bicycles.

For answers, we headed for the most unforgiving terrain we could think of: Moab, Utah. And came back with a suspension glossary.

Compression session

“Shocks and forks all have a little bit of adjustment as far as the compression goes,” says Chad Guyer of Poison Spider Bicycles in Moab. “When we say compression, we mean how much that fork or shock compresses.”


Compression can be controlled by dampening, or limiting, the rate at which the suspension is compressed. “If I feel like the fork dives a little bit, I can tune that out with a little bit of compression dampening,” Guyer says. “Same with the shock.”

Suspension settings

Today’s modern full suspension mountain bike is equipped with suspension that has three simple settings that adjust things on the fly. Many riders will “open up” their compression for downhills, allowing the most travel from their suspension, switching to a firmer setting for uphill battles to save energy transferred from body to bike. Many suspension designs have a middle setting for general trail conditions.

“I have an open, a middle setting, which I consider a trail setting for pedaling, and I have a firm setting which is like a lock out,” Guyer says. “(Adjustments) can be done while the rider is pedaling.”

There’s a feeling in the air

Instead of coil springs, most modern shocks and forks have turned to air chambers to establish their suspension characteristics. When coupled with oil cartridges that control fine tuning, this creates optimal adjustability.

On the rebound

Rebound refers to the rate at which the suspension returns to it’s original position. Faster rebound rates creates a bouncy lively feel, great for small bumps. Slower rebound rates are good for larger bumps. Finding what’s best is up to the rider.

“It depends on your riding style,” Guyer said. “You decide what kind of rider you are and what you’re going to do the most.”


Sag is the amount of travel taken up only by the rider’s body weight. Most suspension designers recommend somewhere around 20 to 30 percent sag.

For a full suspension mountain bike and its adjustments, Guyer advises looking to the owner’s manual for appropriate settings for rider weight and determining rider preference.