Suspension Service: What You Can Do at Home
Most suspension problems are setup, not failure. Set sag, keep the seals clean, and know which jobs are home service and which need a specialist.
Suspension that feels harsh, wallowy or sticky is usually a setup problem or a missed service, not a broken part. Understanding a couple of basics keeps your fork and shock working as intended.
Set sag before anything else
Sag is how much travel the suspension uses under your weight alone, sitting still. For a trail setup, aim for about 20 to 25 percent on a fork and 25 to 30 percent on a rear shock at a 70 kg rider, then adjust air pressure until you get there. Sag is the foundation; damping changes will not fix a wrong spring rate.
- Too much sag: the bike sits low, wallows and bottoms out.
- Too little sag: harsh over small bumps and poor traction.
- Rebound: the wheel should return fast enough to track the ground but not spring past it.
Damping dials, simply
Rebound controls how fast the suspension returns after a bump; too slow and it packs down over repeated hits, too fast and it bounces. Compression controls how firmly it resists being pushed down. Change one click at a time, ride the same loop, and trust your hands over the numbers.
Clean wipers and fresh oil do more for fork feel than any dial. Service intervals exist for a reason.
Cleaning and lower-leg service
Wipe the fork stanchions after every ride and keep the wiper seals clean; grit driven into the seals wears the bushings. A lower-leg service, which means draining and replacing the bath oil and greasing the seals, is a reasonable home job with the right oil and a guide, typically every 50 to 70 hours of riding. Air-can and damper services need tools and experience best left to a suspension specialist.
Air pressure and temperature
Air forks are sensitive to temperature; a cold morning can make the same setting feel firmer. Note your pressures and settings, and check them before a big ride rather than mid-trail. Keep a shock pump at home so you can adjust with confidence.
When to send it in
If a fork loses air, feels gritty through its stroke, or a shock is leaking oil, it is time for professional service. Keep a note of the service dates; most makers recommend a full damper service once a year or after a set number of hours, whichever comes first.
Set sag, keep seals clean, service the lowers on time, and the suspension will keep the trail feeling bigger than it is.
Frequently asked questions
How much sag should my mountain bike have?
About 20 to 25 percent on a trail fork and 25 to 30 percent on a rear shock. Set sag first, then adjust rebound and compression one click at a time.
Can I service my own suspension?
A lower-leg service is a reasonable home job with the right oil and a guide. Damper and air-can services need specialist tools and are best handled by a suspension shop.
How often does suspension need servicing?
Many makers suggest a lower-leg service every 50 to 70 hours and a full damper service roughly once a year, or sooner if the fork loses air or feels gritty.
