Damper

Shocks on bicycles as part of MTB suspension

On mountain bikes, the suspension consists of one or two parts:

• Full-suspension (full-suspension, fully suspended): The suspension consists of a fork (absorbs energy) and a shock (controls its return). The shock regulates the speed of compression and rebound. This influences the system’s ride feel, traction and pedaling efficiency.
  
  
• Hardtail: The suspension is provided exclusively by the fork at the front, while the rear triangle remains rigid. At the rear, bumps are absorbed directly through the frame, tires and riding technique - hardtails do not have a shock-

A well-tuned shock on a full-suspension bike minimizes impacts for the person in the saddle and therefore provides comfort and grip.

Explaining stroke and eye-to-eye length

Stroke refers to the shock’s maximum travel. More stroke means greater reserves on rough trails. Eye-to-eye length is the shock’s total length when unloaded. It must match the frame exactly. Models that are too short or too long alter the geometry and function and can damage your equipment.

Types of bicycle shocks

MTB shocks are divided into air and coil models:

• Air shocks: Lightweight and precisely adjustable via air pressure, ideal for varied uses.
• Coil/coil-spring shocks: Consistent spring rate, highly sensitive to small impacts, perfect for long descents.
• Reservoir shocks: With an external oil reservoir, for demanding applications such as enduro or downhill.

Applications at a glance

1. Cross-country: Short stroke (80–120 mm), usually an air shock for low weight.
2. Trail/All-mountain: Medium stroke (120–150 mm), air or coil depending on preference.
3. Enduro/Downhill: Long stroke (150 mm+), robust construction, often coil or high-volume air shocks.

Important settings

• Compression: Regulates how quickly the shock responds while compressing.
• Rebound: Controls the speed of rebound.
• High-/low-speed damping: Separate adjustment for small bumps and hard impacts.

You generally adjust the shock using the dial or lever directly on the housing. Compression and rebound can be adjusted in steps or continuously, usually with clearly labeled adjustment rings.
Note that you need a special shock pump to set up an air shock’s base settings using air pressure. Always change the air pressure gradually so that you can clearly understand its effect on the bike’s handling.

Frequently asked questions

We answer the most frequently asked questions about bicycle shocks. Find more general information about bicycle suspension or about coil springs and remote controls. 

What does a shock do on a bicycle?

It controls suspension movement, improves traction, protects the rider and frame, and provides greater control.

What is a shock bushing?

A shock bushing is a small, precisely fitting component that securely mounts the shock in the frame. It serves as the connection between the shock eyelet and the mounting bolt on the frame. Shock bushings ensure play-free movement and protect the shock from lateral forces. Depending on the frame and shock model, different sizes and designs are available.

How many bar should be in a bicycle shock?

The air pressure depends on the rider’s weight and desired suspension-adjusted geometry (SAG). It is usually set so that 25–30% of the travel is used while stationary. A shock pump and the manufacturer’s specifications are essential.

What are the disadvantages of bicycle suspension?

More weight, increased maintenance and possible efficiency losses when climbing. With proper setup, however, the advantages usually outweigh the disadvantages.

What is the difference between suspension and damping?

Suspension stores energy (in a spring or air chamber). Damping regulates the return of this energy through oil or valves.

Which shock should I use for my bicycle?

Follow the frame specifications and consider the desired stroke, riding style and weight. Air shocks are often used for XC, while enduro bikes often use coil or high-volume air shocks.

Conclusion: Set up the shock for your intended use

Choose a shock that matches the stroke, eye-to-eye length and intended use. Air for low weight and adjustability, coil for consistency and comfort. Adjusting compression and rebound makes the difference. At raaad.de you will find a wide selection of different shocks - from air shocks for lightweight XC bikes to robust coil shocks for downhill MTBs.