The SID SL Ultimate 2P from RockShox is a lightweight, performance-oriented cross-country suspension fork engineered for speed and precision. Maintaining this component at home not only improves your ride quality but also extends the fork’s longevity. This detailed guide covers everything you need to know about installing, adjusting, and maintaining your SID SL Ultimate 2P, including troubleshooting, compatibility insights, and customization techniques.
Tools Required
- 2mm, 5mm, 6mm hex keys [paid link]
- Torque wrench [paid link] with appropriate bits
- Shock pump
- Suspension grease (RockShox Butter recommended)
- Suspension oil (RockShox 0W-30 and 15wt recommended)
- Clean cloths and gloves
- Lower leg removal tool (non-marring pick or soft mallet)
- Digital caliper [paid link] (optional for bushing and stanchion checks)
Installation Guidelines for SID SL Ultimate 2P
Correct installation is vital for performance and safety. The SID SL Ultimate 2P is designed for 29″ wheels and supports up to 120mm of travel.
Start by verifying that the steerer tube length is appropriate for your frame. Use a proper crown race compatible with your headset system. When cutting the steerer tube, leave sufficient stack height for headset spacers and stem. Always use a star nut or a compression plug if the steerer is carbon.
Insert the fork into the head tube, fit the crown race, spacers, and stem, then torque the top cap bolt to preload the headset. Align and torque the stem bolts to specification. Finish by installing the front brake caliper using the correct post-mount adapter, ensuring rotor size compatibility.
Initial Setup and Adjustment
The SID SL Ultimate 2P features a two-position remote (2P) with “Open” and “Lock” modes. Set sag using a shock pump, targeting 15–20% of the total travel. Rider weight and preference will affect this setting.
Check rebound settings via the red dial on the right leg. Turn clockwise for slower rebound and counter-clockwise for faster rebound. Set it midway and fine-tune based on trail feedback.
If your model includes DebonAir technology, confirm the negative and positive air chambers equalize during setup. This ensures small bump sensitivity and optimal travel usage.
Routine Maintenance Schedule
Regular maintenance is essential for performance. RockShox recommends lower leg service every 50 hours of riding.
Remove the lower legs using a soft mallet and drain the old oil. Clean internals with isopropyl alcohol, inspect bushings, and check stanchions for wear. Replace foam rings and lubricate with RockShox Butter. Reinstall the lower legs with fresh oil—5ml per leg of 15wt in the lowers and 0W-30 in the damper side as required.
Every 100–200 hours, perform a full damper and air spring service. This requires removing the air shaft and damper assembly, cleaning thoroughly, replacing O-rings, and refilling with the correct oil volumes. Follow RockShox service manuals for torque values and oil specs.
Troubleshooting Common Set-Up Issues
If your fork doesn’t compress smoothly, check for air spring imbalance. Equalize chambers by compressing the fork fully.
A clunking noise often indicates dry bushings or loose headset parts. Check torque on the headset and apply fresh lubrication to the bushings during service.
Loss of travel can result from over-inflation or internal air migration. Recheck pressure settings and service the air spring if needed.
Inconsistent lockout function typically relates to improper cable tension or a worn remote. Adjust tension and inspect for damage. Replace the remote if necessary.
Customization for Performance Optimization
Customizing your SID SL Ultimate 2P lets you fine-tune performance based on terrain and personal preferences. One method involves adjusting the volume spacers inside the air spring. Fewer spacers make the fork feel more linear and plush, while more spacers increase bottom-out resistance.
Rebound tuning can also enhance ride feel. Experiment with click settings to optimize control on rough terrain or increase comfort on smoother trails.
For remote lockout performance, consider upgrading to a TwistLoc or hydraulic remote system for more precise actuation. Additionally, switching to lighter oil in colder climates can maintain small bump sensitivity.
Comparing SID SL Ultimate 2P with Similar Models
Compared to the standard SID SL Select+, the Ultimate 2P offers a lighter chassis, more advanced Charger Race Day damper, and premium DebonAir air spring. This makes it better suited for elite XC racing where every gram and millisecond counts.
Unlike the Fox 32 Step-Cast, which uses a similar lightweight build, the SID SL Ultimate has more tuning options and typically better small bump compliance. Riders seeking absolute adjustability might prefer Fox’s FIT4 damper, but for simplicity and performance, the RockShox option remains competitive.
Compatibility with Other Drivetrain and Suspension Components
The SID SL Ultimate 2P fits most modern XC frames with tapered head tubes and 100mm or 110mm boost hub spacing.
Brake compatibility includes post-mount calipers and 160mm to 180mm rotors, depending on the frame and adapter used.
It pairs well with RockShox rear shocks like the SIDLuxe for consistent ride characteristics. When mixing brands, ensure damper performance and spring curves align to prevent front-rear mismatch.
Handlebar-mounted lockout remotes work best with SRAM Matchmaker systems, but adapters are available for Shimano or third-party clamps.
Frequently Asked Questions (FAQs)
How often should I service my SID SL Ultimate 2P?
Perform a lower leg service every 50 hours of ride time and a full damper/air spring service every 100–200 hours, depending on conditions.
What is the correct air pressure for my weight?
Refer to the RockShox air pressure chart. Generally, a rider weighing 70kg should start around 85–90 psi. Adjust based on sag measurement.
Why is my fork losing travel?
Air spring imbalance or internal seal leakage can cause reduced travel. Try equalizing chambers and servicing the air spring.
Can I upgrade the remote lockout system?
Yes, the SID SL Ultimate 2P supports upgrades to the TwistLoc or hydraulic lockout remotes for smoother operation.
Is this fork compatible with 27.5″ wheels?
No, the SID SL Ultimate 2P is specifically designed for 29″ wheels. Using a different size can compromise performance and safety.
What’s the maximum tire clearance for this fork?
It supports up to a 2.4″ tire depending on the rim and tire model. Always check clearance under full compression before riding.
Conclusion
Proper care and thoughtful adjustments of your SID SL Ultimate 2P suspension fork ensure that it performs to its fullest potential on every ride. By following the installation, tuning, and maintenance practices outlined here, you’ll keep your fork responsive, durable, and race-ready—all from your home workshop.