The RockShox SID SL Ultimate 3P suspension fork is a high-performance, lightweight option designed for competitive cross-country riding. With its three-position damper (Open, Pedal, Lock), integrated Race Day 2 damper system, and exceptional chassis stiffness-to-weight ratio, it demands precise setup for optimal performance. This guide covers the essential adjustments, maintenance routines, and troubleshooting techniques to ensure your SID SL Ultimate 3P delivers peak efficiency on every ride.
Tools Required
- Shock pump (with precise pressure gauge)
- Torque wrench [paid link] with 3-5 Nm range
- 2mm to 6mm hex wrenches
- Suspension setup guide or app (optional)
- Clean cloth and isopropyl alcohol
Understanding the SID SL Ultimate 3P System
The SID SL Ultimate 3P uses a Race Day 2 damper offering three distinct compression settings: Open, Pedal, and Lock. These are engaged via a remote or top crown lever. The system is optimized for racing efficiency, with minimal weight and maximum sensitivity. Adjusting it requires understanding both air spring and damper behavior.
Setting Sag and Air Pressure
Proper sag (typically 15-20% for XC) is foundational for performance.
Start by determining your rider weight in full gear. Use RockShox’s suspension calculator or chart to estimate initial air pressure. Remove the fork cap with a 2mm hex key and attach the shock pump.
Sit on the bike in riding position and observe sag using the rubber o-ring on the stanchion. Adjust air pressure incrementally to reach your target sag. Always reset the o-ring before checking again to ensure accuracy.
Too much sag leads to bottom-outs, while too little creates a harsh ride. Fine-tune for personal riding style—slightly more sag for comfort, less for aggressive terrain responsiveness.
Compression Adjustments: Open, Pedal, Lock
Each damper mode changes the fork’s response characteristics:
- Open Mode provides maximum sensitivity and is ideal for descents and rough trails.
- Pedal Mode introduces low-speed compression damping, reducing fork bob and preserving energy while climbing or sprinting.
- Lock Mode effectively rigidifies the fork for smooth terrain, offering maximum power transfer.
Use the remote lever or top cap switch to engage each mode. Transitions should be clean and immediate. If you experience hesitation or misalignment, check cable tension or lever position.
Rebound Setting for Ride Control
Rebound controls how quickly the fork returns after compression. This is adjusted at the bottom of the right fork leg via a red dial.
Set rebound by pressing the fork fully and allowing it to extend. If it returns too fast and tops out sharply, slow the rebound. If it feels sluggish, speed it up. A well-set rebound recovers in sync with your riding tempo without bouncing or diving.
A general rule: start in the middle setting and adjust after test riding. Cross-country riders often prefer a faster rebound for better terrain tracking at speed.
Routine Maintenance
For longevity and consistent performance, routine servicing is essential.
Every 25 hours of riding:
- Wipe down stanchions post-ride.
- Inspect dust seals for dirt ingress or wear.
- Add suspension oil to foam rings if dry.
Every 50 hours:
- Perform a lower leg service.
- Replace wiper seals if worn.
- Check for bushing play or damper fluid discoloration.
Use only RockShox-recommended lubricants and fluids. Follow torque specifications when reassembling components.
Troubleshooting Common Setup Issues
Fork feels harsh in Open mode: Verify correct sag and air pressure. Reduce air slightly and check for adequate lubrication in the air spring.
Remote not engaging all positions: Inspect cable routing for sharp bends or friction. Check tension and lever mounting. Recalibrate using the barrel adjuster or reattach the cable at the fork-side clamp.
Loss of travel or soft feel: May indicate air spring leak or insufficient air pressure. Confirm PSI with a shock pump and look for oil or air leaks around the air valve.
Unusual noises (squelching or clicking): May stem from damper cavitation or dirty internals. A damper service may be required if noises persist after a lower leg service.
Customization and Performance Optimization
The SID SL Ultimate 3P supports several tuning options for rider-specific performance:
- Air volume tokens: Installing tokens increases ramp-up to resist bottoming out. Remove tokens for a more linear feel.
- Remote customization: Choose between twist or push-button levers. Opt for MatchMaker integration for a cleaner cockpit.
- Aftermarket upgrades: Titanium bolts and custom decals offer minor weight savings and personalization without affecting function.
Compatibility Considerations
This fork is designed for 29” wheels with up to 100mm travel, compatible with flat-mount disc brakes and 44mm offset. The steerer is tapered and must match your frame’s head tube.
Ensure your frame accepts the 100mm axle spacing and 15x110mm Boost hub standard. The 3P remote is compatible with SRAM MatchMaker systems and most standard handlebars.
Use only RockShox-specific replacement parts and adhere to maximum rotor size recommendations (180mm) to prevent warranty voiding.
Comparing SID SL Ultimate 3P with Other Models
Compared to the standard SID SL Ultimate (2P), the 3P model offers an added middle mode—Pedal—which allows for greater terrain adaptability. This mode is especially useful for riders who encounter varied gradients and want to avoid excessive handlebar toggling.
Versus Fox’s 32 Step-Cast, the SID SL Ultimate 3P is lighter and slightly stiffer in lateral deflection tests. However, the Fox model offers slightly more mid-stroke support out of the box. The SID wins in weight-conscious race builds, while Fox may suit more aggressive riders needing extra damping.
Conclusion
The RockShox SID SL Ultimate 3P delivers elite-level performance when adjusted precisely. By fine-tuning sag, compression modes, and rebound, and maintaining the fork regularly, riders can ensure efficient, responsive suspension on every ride. Whether climbing steep fire roads or descending twisty singletrack, this fork excels in conditions where efficiency and weight matter most. Proper setup not only maximizes speed but also enhances long-term durability and confidence on technical terrain.