The Campagnolo Bora One hub is a precision-engineered component that demands careful handling when performing maintenance. Proper bearing replacement and servicing not only restore smooth rotation but also extend the life of the wheel. This guide explains how to correctly replace and service the bearings in both the front and rear Bora One hubs[paid link], with detailed technical steps and practical insights from professional road bike mechanics.
Tools Required
- 5 mm and 10 mm hex wrenches
- Bearing puller or extractor
- Campagnolo HB-BO001 bearing drift set (or equivalent)
- Soft-faced mallet
- Campagnolo grease (or a high-quality low-friction bearing grease)
- Torque wrench[paid link]
- Clean lint-free cloths
- Degreaser and isopropyl alcohol
- Bearing press[paid link] tool compatible with 6803 and 6903 cartridge bearings
Understanding the Bora One Hub Bearing System
The Bora One hubs[paid link] use sealed cartridge bearings that provide smooth, low-friction rolling with minimal maintenance. Campagnolo designs these hubs for both performance and durability, using high-quality steel bearings that are pressed into the hub shell and freehub body.
The front hub typically houses two 6803 bearings, while the rear hub uses two 6903 bearings in the hub shell and two smaller bearings within the freehub body. Understanding this configuration is crucial before beginning any service procedure.
Campagnolo hubs are built with adjustable cup-and-cone end caps, allowing fine preload adjustments after bearing installation. This adjustment system prevents lateral play and maintains optimal rolling efficiency.
Removing the Bora One Hub Axle and Bearings
Servicing begins with the careful disassembly of the hub. The Bora One’s design allows relatively straightforward removal, but precision and cleanliness are essential.
- Remove the wheel from the frame and take off the quick-release skewer or thru-axle.
- Loosen the end caps using the appropriate hex wrenches. For the rear hub, insert the 10 mm hex key into the drive-side end and a 5 mm key into the non-drive side, then rotate counterclockwise.
- Slide the axle out of the hub body carefully to avoid damaging the bearing seats.
- Using a bearing puller, gently extract the bearings from the hub shell. Always pull the bearing straight to prevent scoring or deformation of the bearing seats.
If you encounter resistance, avoid prying with screwdrivers or similar tools, as this can distort the aluminum hub body. Instead, reapply the extractor evenly or use a hub support block to ensure the force is distributed correctly.
Cleaning and Inspecting the Hub Shell
After removing the bearings, clean all internal surfaces thoroughly. Any contamination inside the bearing seat can accelerate wear or cause uneven loading once new bearings are installed.
- Use degreaser and a soft cloth to remove old grease and dirt.
- Follow up with isopropyl alcohol to eliminate residue.
- Inspect the bearing seats for pitting, corrosion, or ovalization. If these are present, professional machining or hub replacement may be necessary.
For the rear hub, also inspect the freehub body and ratchet engagement surfaces. Clean the pawls and reapply a thin layer of Campagnolo-approved grease to ensure crisp engagement.
Installing New Bearings in the Bora One Hub
Reinstalling the bearings requires care to ensure they seat correctly without introducing preload or misalignment.
- Align the new bearing with the hub shell opening.
- Use the bearing press tool and correct drift adapter to push the bearing straight into position. Apply pressure only on the outer race of the bearing.
- Repeat for the second bearing on the opposite side.
- Once seated, check that both bearings are fully flush and evenly positioned within the hub shell.
For the rear hub, repeat the process for the freehub body bearings. Use a smaller drift and support the body evenly during pressing to avoid distortion.
Reassembling the Hub and Setting Bearing Preload
Once the bearings are in place, the axle and end caps can be reinstalled.
- Insert the axle gently through the hub, ensuring it passes cleanly through both bearings.
- Reattach the end caps and tighten them finger-tight initially.
- With the wheel in your hand, spin the hub to feel for smoothness.
- Using a torque wrench[paid link], tighten the end caps to Campagnolo’s specification—typically 12 Nm for Bora One hubs.
- Adjust the bearing preload using the micro-adjust collar on the non-drive side. Turn clockwise until all play is removed, then back off slightly (about one-eighth of a turn) to prevent over-preload.
An over-tightened bearing will feel rough and resist rotation, while an under-tightened one will cause lateral play. Proper adjustment ensures the hub spins freely with no side movement.
Maintenance and Service Interval Recommendations
To maintain the Bora One hub’s performance, routine bearing checks should be integrated into your maintenance schedule. Campagnolo recommends inspection every 3,000–5,000 km, or sooner under wet or dusty conditions.
- Lightly clean the hub exterior after every ride.
- Inspect for play by rocking the rim side to side; if movement is detected, readjust the preload.
- Regrease bearings annually if the bike is used in harsh weather or during long-distance events.
Replacing the bearings every 10,000–12,000 km—or when roughness is felt—keeps rolling resistance low and ensures consistent performance.
Troubleshooting Common Issues After Bearing Replacement
If issues persist after servicing, consider the following checks:
- Roughness persists: Bearings may be over-preloaded or misaligned. Recheck the seating and back off the preload slightly.
- Lateral play: The end caps may be under-tightened, or the preload collar may have loosened. Retighten to specification.
- Noise during rotation: Dirt or excess grease inside the freehub can cause uneven engagement. Disassemble and clean the mechanism.
- Uneven bearing wear: This often indicates improper installation force or contamination inside the hub shell.
Regular inspection and precise installation eliminate most of these issues.
Compatibility and Bearing Options
The Bora One hub accepts standard 6803 (front) and 6903 (rear) cartridge bearings. Riders may choose to upgrade to ceramic bearings for reduced rolling resistance, though this offers minimal performance gain unless maintained with exceptional care.
When replacing bearings, always match the original dimensions and type specified by Campagnolo. Avoid third-party bearings with different tolerances, as these can cause premature wear or fitment issues.
Conclusion
Replacing or servicing the bearings in your Campagnolo Bora One hub requires precision, patience, and attention to detail. Following the correct procedure ensures optimal rolling efficiency, longer component lifespan, and consistent performance under all riding conditions.
By maintaining clean bearing seats, applying the proper grease, and setting preload accurately, you preserve the engineering integrity that makes Campagnolo hubs a benchmark in road cycling performance.