The Complete Guide to Mountain Bike Suspension Service Intervals

Why Hours and Miles Both Miss the Point

Fox recommends lower leg service every 50 hours. RockShox says 50 hours for a basic service, 200 hours for a full. These are reasonable starting points — but they treat all hours equally.

An hour of fire road climbing barely moves your fork. An hour of steep, rocky descents compresses it hundreds of times under high force. Your seals, oil, and damper are working dramatically harder in the second scenario. Counting hours without weighting for the type of riding misses the most important variable.

What Actually Determines Service Need

• 1.
  Descent frequency and severity. Every descent compresses your suspension. Steeper, rockier, longer descents create more compression cycles and higher forces. A lift-accessed bike park day puts significantly more stress on your fork compared to an XC ride of the same duration.
• 2.
  Trail conditions. Dust and fine dirt work past seals and contaminate oil. Mud is even worse. Wet rides accelerate seal wear and introduce moisture into the damper. Suspension serviced after a muddy season will look dramatically different than after dry-condition riding.
• 3.
  Rider weight and bike setup. Heavier riders compress suspension harder, creating more seal friction and damper stress. A 200-pound rider on the same trail as a 140-pound rider will need service sooner.
• 4.
  Temperature. Oil viscosity changes with temperature. Riding in extreme cold or heat affects damper performance and seal pliability. Cold weather can cause seals to leak prematurely.

Fork vs. Shock: Different Wear Profiles

Your fork and rear shock experience different forces. The fork takes direct trail impacts — every rock, root, and drop hits it first. The rear shock is filtered through the bike's linkage, which dampens and redirects forces.

Forks generally need service more frequently. Lower leg services (cleaning seals and refreshing bath oil) should happen before full damper services. If you're only tracking one thing, track fork service first.

Signs Your Suspension Needs Service

• Oil weeping from lower legs or stanchions
• Stiction (fork sticking instead of moving smoothly)
• Harsh feel on small bumps (contaminated oil)
• Clunking or knocking sounds
• Loss of damping control (bouncing without recovery)

Descent-Weighted Tracking

Trail Hits takes a different approach to suspension service tracking. Instead of counting hours, it analyzes GPS data to identify descents — their steepness, duration, and elevation loss. Each descent gets weighted by its severity. The result is a suspension health score that reflects what your fork and shock actually experienced, not a generic timer.

Combined with condition multipliers (mud, wet, dust) and the Problem Solver for tuning, you get a complete picture of your suspension health and performance.