MTB Forks

What is an MTB fork and what is its main purpose?

In Dirt Jump and Slopestyle, the fork has two tasks: it must dampen hard landings to protect your wrists and frame, but it must not sag in the transition during take-offs. Therefore, these forks are tuned significantly stiffer than classic trail forks.

How is an MTB fork constructed?

Steerer Tube

The connection to the frame. Modern DJ bikes almost always use Tapered steerers (1.5 inch bottom, 1 1/8 inch top) for maximum stiffness.

Stanchions & Lowers

On suspension forks, the upper stanchions glide into the lower legs. A diameter of 32mm to 35mm is common here for high stability.

Thru-Axle

Instead of quick releases, massive 15mm or 20mm thru-axles are used to fix the front wheel rigidly.

What types are there?

• Dirt Jump Suspension Forks: Usually 100mm travel. They have very hard air suspension and strong compression damping so they don't swallow energy when pushing in a pumptrack or taking off.
• Rigid Forks: For pure Street MTBs or park riders who want the most direct feel. They are lighter and maintenance-free but forgive no mistakes.

How do I install an MTB fork?

1. Install the crown race onto the steerer (or use a split race).
2. Cut the steerer tube to the appropriate length (account for stem height + spacers!).
3. Drive the Star Nut into the steerer tube.
4. Grease the bearings, insert the fork, and install the stem and spacers.
5. Tighten the top bolt until play is eliminated, then clamp the stem.

What do the specifications mean?