The RockShox SID Ultimate 3P is a premium-level XC suspension fork built for precision, weight savings, and aggressive race performance. Designed for riders who demand top-tier responsiveness and adjustability, the SID Ultimate 3P integrates three-position compression control (Open, Pedal, Lock) for on-the-fly tuning. To ensure peak performance and fork longevity, regular servicing is essential. This guide walks you through the complete process of servicing your SID Ultimate 3P at home, including installation, setup, maintenance, troubleshooting, and performance optimization.
Tools Required
- Torque wrench [paid link] with 4mm, 5mm, and 6mm hex bits
- Flat-blade screwdriver
- Suspension oil (RockShox 0W-30 and 5W)
- Clean rags or paper towels
- Isopropyl alcohol (99%)
- Shock pump
- Pick tool or dental pick
- RockShox lower leg service kit (includes wiper seals and crush washers)
- Suspension grease (Slickoleum or RockShox Dynamic Seal Grease)
- Plastic syringe or oil damper tool
- Seal press tool or deep socket set (32mm or 35mm)
- Clean workstand
Understanding the SID Ultimate 3P System
The SID Ultimate 3P uses a Charger Race Day damper and a DebonAir+ air spring, both optimized for XC speed and efficiency. The fork offers three damper modes controlled via a handlebar-mounted remote or crown switch, allowing riders to choose Open, Pedal, or Lock modes depending on terrain.
The service intervals are as follows:
- Lower leg service every 50 hours
- Damper and air spring service every 100-200 hours, or yearly
Removing the Fork for Service
Begin by removing the fork from the bike to access all necessary components. Disconnect the front brake caliper and rotor, remove the front wheel, and slide the fork out of the headset after loosening the stem and headset spacers. Use care to not damage the steerer tube.
Wipe down the fork completely and inspect for scratches, oil seepage, or bushing wear before continuing.
Performing a Lower Leg Service
Servicing the lower legs restores suspension smoothness and prevents premature wear.
Step 1: Drain the Old Oil
Lay the fork horizontally. Use a 2.5mm hex key [paid link] to remove the damper and air side bottom bolts. Gently tap each bolt to dislodge the lower legs, allowing excess oil to drain.
Step 2: Clean the Internals
Remove the lowers completely. Wipe clean the stanchions, damper shaft, and air shaft with isopropyl alcohol. Inspect for contamination or signs of wear.
Step 3: Replace Seals and Lubricate
Remove the old wiper seals using a flat-blade screwdriver. Press new wiper seals into place using a seal press. Apply a thin film of suspension grease inside the new seals.
Air Spring Service: SID DebonAir+
The DebonAir+ system offers smoother small-bump sensitivity and better mid-stroke support.
- Remove the top cap of the air spring with a cassette tool.
- Slide out the air shaft and clean all components.
- Replace the shaft o-rings and apply suspension grease.
- Reinstall and torque the top cap to RockShox specifications.
Damper Service: Charger Race Day 3P
Servicing the damper requires attention to oil volume and cleanliness.
- Carefully remove the damper from the fork crown.
- Drain and dispose of old damper oil.
- Clean the damper shaft and internal chamber using isopropyl alcohol.
- Refill with RockShox 5W damper oil using a syringe.
- Bleed air bubbles and reassemble with correct torque settings.
Due to the sealed design, full damper overhauls may require factory-level tools and are best left to professionals if you’re unfamiliar.
Reassembling the Fork
With the damper and air spring serviced:
- Slide the lowers back onto the stanchions slowly.
- Add 10ml of 0W-30 suspension oil into each lower leg.
- Reinstall bottom bolts and torque to specifications.
- Check for smooth compression and rebound action.
Installing the Fork Back onto the Bike
Slide the fork into the headset and reinstall spacers, stem, and headset cap. Torque all bolts evenly to manufacturer settings. Reattach the front brake and ensure rotor clearance is correct. Reinstall the front wheel and verify correct axle torque.
Suspension Setup: Dialing in SID Ultimate 3P
Use a shock pump to set sag based on your weight (15-25% of total fork travel). The RockShox setup guide offers rider-specific air pressure recommendations.
Set rebound and compression based on terrain:
- Open for descending
- Pedal for rolling terrain
- Lock for sprints or climbs
Fine-tune rebound using the red adjuster on the fork leg.
Common Troubleshooting Issues
- Loss of Travel or Harsh Top-Out: Check air spring service intervals and top-out bumper wear.
- Excessive Rebound or Lack of Damping: May indicate low damper oil level or air in damper—bleed and refill.
- Oil Leaking Around Seals: Replace wiper seals and ensure proper lubrication.
- Handlebar Remote Not Switching Modes: Check cable tension and housing friction; replace or re-lube as needed.
Performance Optimization Tips
For racers and advanced riders:
- Use volume spacers to alter air spring progression.
- Adjust remote tension for quicker 3P transitions.
- Consider using friction-reducing additives like Butter Grease around seals.
These changes can drastically enhance mid-stroke support and responsiveness on technical terrain.
Compatibility with Other Drivetrain and Suspension Components
The SID Ultimate 3P uses a Boost 110mm axle spacing and is designed for 100–120mm XC setups. It’s fully compatible with SRAM TwistLoc remotes and RockShox rear shocks using 3P lockout systems.
For drivetrain clearance, the SID crown and arch provide room for wide tires (up to 2.4″) and chainring configurations on 1x drivetrains.
Comparison: SID Ultimate 3P vs Other RockShox XC Forks
- SID SL Ultimate: Lighter, but lacks 3P compression; better for pure racing.
- SID Select+: Similar chassis but uses a simpler damper; less adjustability.
- RockShox Reba: Heavier and more basic; best for budget-conscious riders.
The SID Ultimate 3P stands out with its race-focused chassis, ultra-light Charger Race Day damper, and fully independent 3-position control.
Frequently Asked Questions (FAQs)
Q1. How often should I service my SID Ultimate 3P fork?
Service the lower legs every 50 hours and perform a full damper and air spring service every 100-200 hours or once per year.
Q2. Can I use other brands of suspension oil?
Always use RockShox-approved suspension oils to maintain performance and avoid seal damage.
Q3. My remote isn’t changing modes—what’s wrong?
Check the cable tension and housing routing. Replace frayed cables and ensure the remote mechanism is clean and lubricated.
Q4. Can I increase the travel of my SID Ultimate 3P?
Yes, travel can typically be adjusted between 100–120mm by changing the air shaft. Consult RockShox documentation for details.
Q5. What tire size fits the SID Ultimate 3P?
It accommodates up to a 29×2.4″ tire with sufficient mud clearance.
Q6. Do I need to remove the fork for basic maintenance?
For lower leg service, removal is highly recommended to ensure full cleaning and lubrication access.