RockShox Fork & Rear Shock Setup Calculator
Use this to get a practical starting pressure and sag target. Then fine-tune after a short trail test.
How this RockShox air pressure calculator helps
Dialing air pressure is the fastest way to improve comfort, grip, and control. Too much pressure and the bike feels harsh and skittish. Too little pressure and it rides low, wallows in corners, and bottoms out too easily. This calculator gives you a practical baseline for fork PSI, rear shock PSI, and sag targets so your first ride is already close.
It is designed as a rider-friendly setup tool, not an official RockShox chart replacement. Every bike frame and damper tune is different, so expect to adjust by 5–15 PSI after your first trail session.
What the calculator uses
- Rider system weight: body + hydration pack + kit + tools.
- Riding style preset: XC, Trail, Enduro, or DH changes support and sag target.
- Travel and leverage ratio: helps estimate realistic rear shock pressure.
- Sag guidance: gives front and rear targets in both percent and millimeters.
Typical sag targets by discipline
| Discipline | Fork Sag | Rear Sag | Ride Feel |
|---|---|---|---|
| XC / Marathon | 16–20% | 22–26% | Efficient pedaling, firm platform |
| Trail | 18–22% | 25–30% | Balanced comfort and support |
| Enduro | 20–25% | 28–32% | More grip and bump absorption |
| DH / Bike Park | 22–28% | 30–35% | Maximum traction and control on rough tracks |
How to set up your RockShox suspension in 6 steps
1) Pump to the calculator value
Use a shock pump and inflate fork and rear shock to the recommended start PSI.
2) Equalize air chambers
After each pressure change, compress the suspension 5–8 times through 25–35% travel. Re-check PSI.
3) Set sag in riding position
Wear full gear, stand centered on pedals, and gently settle into neutral stance. Measure sag at fork and shock O-rings.
4) Adjust rebound
Start in the middle of rebound clicks. If the bike feels pogo-like, slow rebound. If it packs down in repeated hits, speed it up.
5) Add compression only after sag is correct
Use low-speed compression for pedal support and cornering stability. Keep changes small, one or two clicks at a time.
6) Test one variable at a time
Do short loop repeats. Change pressure in 3–5 PSI steps and note handling, bottom-outs, and grip.
Troubleshooting pressure and sag
- Feels harsh on roots: reduce 3–5 PSI or open rebound/compression slightly.
- Frequent bottom-outs: add 5–10 PSI and/or volume spacers (tokens).
- Front washes in flat turns: reduce fork PSI slightly or speed up rebound one click.
- Rear bobs while climbing: add 3–5 PSI or add a touch of low-speed compression.
- Bike sits too low in travel: raise pressure and check sag again.
Important notes
This is a starting-point tool for air-sprung RockShox-style setups. Maximum pressure limits vary by component. Always follow your fork and shock manual, and never exceed the pressure printed on the product.
Temperature and elevation can shift pressure slightly. Check PSI before big rides, especially if conditions changed overnight.