Rebuilding the RXF38 m.2 [paid link] suspension fork is an essential maintenance task that ensures optimal performance and longevity of your bike’s front suspension. This Öhlins fork is known for its high performance and precision, making it a favorite among serious riders. Whether you are doing a routine service or need to replace worn-out parts, this step-by-step guide will walk you through the entire process.
Tools Required
- 5mm and 6mm Allen wrenches [paid link]
- 10mm and 13mm spanners
- Suspension fork oil
- Small torque wrench [paid link] (for precise tightening)
- Ohlins RXF38 m.2 [paid link] service kit
- Clean rags and gloves
- 10W and 15W suspension oil (as per specific fork requirements)
- Oil drain pan
- Fork seal driver
- Syringe or oil pump (for precise oil measurement)
Preparing for the Rebuild
Before diving into the rebuild process, it’s essential to prepare your workspace and ensure you have all the required tools and parts.
Start by ensuring that the bike is properly secured in a stand. This will allow you to work comfortably and safely without risking damage to the bike. Gather all the necessary tools, and always wear gloves to keep dirt and oil from contaminating your fork parts.
Also, keep a clean rag handy for wiping down any excess oil during the process. Finally, make sure your new suspension fork oil and parts are ready, including the oil and seals from the Öhlins RXF38 m.2 service kit.
Disassembling the RXF38 m.2 Fork
Step 1: Remove the Fork from the Bike
First, remove the front wheel from the bike. Then, use the 6mm Allen wrench [paid link] to remove the brake caliper and disconnect any cables or wires attached to the fork.
Next, using the appropriate wrench, remove the headset nut and the fork’s upper bolt. Gently slide the fork out from the headset.
Step 2: Drain the Suspension Oil
Place the fork in a secure position to begin draining the suspension oil. Use the 5mm Allen wrench [paid link] to remove the rebound and compression knobs from the fork, allowing the oil to drain out completely. You may need to gently tap the fork to help the oil flow out.
Once the oil has drained, wipe down the fork legs and other components with a clean rag. Make sure all excess oil is removed.
Step 3: Remove the Fork’s Lowers
Use a 10mm spanner to unscrew the bolts securing the fork’s lowers (the lower legs) to the rest of the fork. Once the bolts are removed, carefully slide the lowers off. Be sure to remove any residual oil and clean the components as you go.
If there is any debris or dirt in the lowers, take extra care to clean and inspect them before reassembling.
Step 4: Remove the Air Spring and Dampers
Once the lowers are removed, use the 6mm Allen wrench to unscrew and remove the air spring assembly. Following this, remove the damper from the fork leg. At this stage, you should carefully inspect both parts for any wear or damage. If necessary, replace the air spring or damper with new components.
Cleaning and Inspection
Step 5: Clean All Fork Parts
Use a clean rag to wipe down all internal and external parts of the RXF38 m.2 fork. Pay close attention to areas with seals, bushings, and oil bath. It’s crucial to remove all dirt and debris, as contaminants can impair performance.
Check the stanchions for any signs of wear, scratches, or damage. Damaged stanchions will need to be replaced, as they can severely affect the performance of the suspension and lead to oil leaks.
Step 6: Inspect the Seals and Bushings
Inspect the seals and bushings carefully. If you notice any signs of wear, cracks, or excessive stiffness, replace them with fresh components from the service kit. Worn seals can lead to oil leakage, while damaged bushings can create an unstable ride.
Rebuilding the Fork
Step 7: Reassemble the Air Spring and Damper
After the cleaning and inspection, begin the rebuild by inserting the air spring assembly back into the fork. Tighten the retaining bolts with the 6mm Allen wrench to the torque specifications provided in the service manual.
Next, insert the damper into its corresponding fork leg and secure it in place. Again, tighten it to the specified torque to ensure proper performance.
Step 8: Install New Seals and Lubricate
Install the new seals from the Öhlins RXF38 m.2 service kit into the lowers. Use the seal driver to press the seals into place, ensuring they fit perfectly into the fork legs. Once the seals are in place, lubricate them with a small amount of suspension oil to ensure smooth movement and reduce friction.
Step 9: Reattach the Lowers to the Fork
Carefully slide the lowers back onto the fork’s upper section. Align the holes for the bolts and secure them with the appropriate spanner. Tighten the bolts to the recommended torque value. Make sure the lowers are positioned properly and there are no gaps or misalignments.
Step 10: Add New Suspension Oil
Now, add the appropriate suspension oil into the fork. Use a syringe or oil pump to ensure precise measurement, and refer to the Öhlins RXF38 m.2 service manual for the correct oil volumes and types (typically 10W or 15W).
Start by adding oil to the air spring leg, then to the damper leg. You should check the oil level once the oil has settled, adjusting as necessary to meet the correct specifications.
Step 11: Install the Fork’s Compression and Rebound Dials
Once the oil has been added, reattach the rebound and compression dials to the fork. Tighten them gently to avoid damaging the threads. Ensure that the knobs are functioning smoothly and are free of any oil or dirt.
Final Checks and Testing
Step 12: Test the Fork’s Movement
Before reattaching the fork to the bike, perform a few compressions to ensure that the fork is functioning smoothly. If you notice any unusual stiffness or roughness, double-check your assembly and oil levels.
Step 13: Reinstall the Fork on the Bike
Once you’re confident that the fork is properly rebuilt, reinstall it on your bike. Follow the same steps in reverse, ensuring all bolts are tightened to the correct torque values. Reattach the front wheel, brake caliper, and any cables or wires that were disconnected during the removal.
Troubleshooting Common Set-up Issues
- Fork feels too soft or too stiff: This is usually due to incorrect air pressure or oil levels. Adjust the air pressure or oil volume according to the rider’s weight and preferences.
- Fork makes a knocking sound: A common issue after rebuilds is improper lubrication of the bushings. Check to make sure there is adequate grease or oil around the bushings and seals.
- Leaking oil: If you notice oil leaking from the lowers, the seals may not have been installed correctly. Double-check the seals and reassemble carefully.
Customization and Optimization
- Adjusting air pressure: To optimize your RXF38 m.2 fork’s performance, adjust the air pressure based on your weight and riding style. Increasing the pressure will stiffen the fork, while decreasing it will make the fork more plush for rough terrain.
- Fine-tuning compression and rebound: The compression and rebound settings are critical for adapting to different trail conditions. Start with the factory settings and fine-tune based on your preferences. If you’re unsure, consult with a suspension expert for advice on optimal settings.
Conclusion
Rebuilding the RXF38 m.2 suspension fork may seem daunting at first, but with the right tools and careful attention to detail, you can restore your fork to like-new performance. Regular maintenance will keep your suspension working efficiently, providing a smoother, more controlled ride. Always ensure that you’re using the correct parts and follow the service manual to achieve the best results.