The Campagnolo Bora One hubs [paid link] are renowned for their smooth rolling performance and exceptional build quality, making them a top choice among professional and enthusiast road cyclists. However, even the most precise components can develop roughness over time if the hub bearings are not properly adjusted or maintained. This guide provides a detailed, step-by-step explanation of how to diagnose, adjust, and restore the silky smoothness that defines the Bora One [paid link] hub system.
Understanding the Bora One Hub Bearing System
The Campagnolo Bora One [paid link] hub uses adjustable cup-and-cone bearings, a design chosen for its fine-tuning capability and low friction when correctly set. Unlike sealed cartridge systems, this traditional configuration allows micro-adjustments for optimal preload.
Each hub features hardened steel bearing races, high-quality loose steel bearings, and a micro-adjustment collar on the axle end. This collar enables precise control over bearing preload without the need for disassembly. Proper adjustment ensures minimal resistance, no lateral play, and long bearing life.
If your Bora One hub feels rough, gritty, or develops play, the issue is almost always linked to bearing preload, contamination, or insufficient lubrication.
Tools Required
- 5 mm Allen key
- 17 mm cone wrench [paid link]
- Torque wrench [paid link] (optional but recommended)
- High-quality bicycle grease (Campagnolo recommends lithium-based grease)
- Clean lint-free cloths
Diagnosing Roughness in Bora One Hubs
Before adjusting, it’s essential to determine the cause of roughness. Rough or draggy bearings can stem from multiple issues, not all of which require tightening.
- Axle Spin Test – Remove the wheel from the bike and hold the axle ends with your fingers. Rotate it. If you feel a gritty texture or tightness, there’s likely contamination or excess preload.
- Side Play Check – Grip the axle and push it side-to-side. Any detectable lateral movement indicates insufficient preload.
- Noise Assessment – Clicking or grinding noises while spinning often signal dirt inside the bearing races or dried-out grease.
If the bearings feel dry, cleaning and regreasing should precede any adjustment. Never tighten bearings to mask contamination.
Adjusting the Bora One Bearing Preload
The Bora One hub features Campagnolo’s Micro Adjustment System, located on the non-drive side. This system uses a threaded ring and locknut combination to finely tune bearing tension.
Step 1: Prepare the Wheel
Remove the quick release skewer or thru-axle to prevent compression during adjustment. Place the wheel in a truing stand or hold it securely on a flat workbench.
Step 2: Loosen the Locknut
Using a 17 mm cone wrench [paid link], gently loosen the thin locknut on the non-drive side. Hold the adjustment ring steady while doing this to prevent over-rotation.
Step 3: Adjust the Preload
With the locknut loose, rotate the micro-adjustment ring clockwise to increase preload or counterclockwise to reduce it. Adjust in very small increments — even a quarter turn can make a noticeable difference.
The goal is to achieve zero play while maintaining smooth, resistance-free rotation.
Step 4: Re-tighten the Locknut
Once satisfied with the adjustment, hold the micro-adjustment ring in position and tighten the locknut securely. This ensures the preload remains stable under riding forces.
Step 5: Test the Hub
After tightening, spin the wheel by hand. The axle should rotate freely without any side movement. If roughness remains, disassembly and cleaning may be necessary.
Cleaning and Greasing the Bearings
When adjusting doesn’t eliminate roughness, the issue may lie deeper within the hub bearings. Over time, road grime and water ingress degrade the grease, causing friction and pitting.
Disassembly
Remove the axle assembly by loosening both end caps. Carefully withdraw the axle, keeping track of bearing orientation.
Cleaning
Wipe the bearing cups and cones thoroughly with a lint-free cloth. Use a mild degreaser if contamination is severe, ensuring all old grease and grit are removed.
Inspection
Check for any scoring or dull patches on the races. Replace bearings or cones if visible damage is present, as roughness cannot be corrected through adjustment alone.
Lubrication
Apply a thin, even layer of fresh grease inside the bearing cups. Reinsert the loose bearings, ensuring full coverage. Avoid overpacking, as excess grease increases drag.
Reassembly and Final Adjustment
Reinsert the axle and repeat the micro-adjustment procedure outlined earlier. Properly serviced bearings should feel fluid and free from resistance when spun.
Common Causes of Rough Bearings
Several common factors can cause Bora One hub bearings to feel rough or tight. Addressing these early prevents premature wear.
- Overtightened Preload: Excessive bearing tension increases friction and causes premature pitting.
- Contaminated Bearings: Dirt and water intrusion quickly degrade grease and create roughness.
- Improper Lubrication: Insufficient or incorrect grease results in metal-to-metal contact.
- Worn Bearing Races: If roughness persists after servicing, inspect the cups and cones for wear.
Optimizing Hub Performance
To maintain optimal performance, periodic servicing is essential. Campagnolo recommends inspecting Bora One hubs [paid link] every 3,000–5,000 km or after prolonged wet riding.
Regular cleaning, timely grease replacement, and correct preload adjustment ensure long-term smoothness and efficiency. Avoid using degreasers or solvents directly on sealed areas, as they can compromise lubrication.
A correctly adjusted Bora One hub should spin freely with no side play, providing a responsive and frictionless ride that reflects Campagnolo’s precision engineering.
Comparison: Bora One vs. Bora Ultra Hubs
While the Bora One shares many features with the higher-end Bora Ultra, key differences exist in the bearing system. Bora One hubs use steel bearings, whereas Bora Ultra models utilize USB (Ultra Smooth Bearings) or CULT (Ceramic Ultimate Level [paid link] Technology) ceramic bearings.
Despite this, both systems rely on identical adjustment principles. When correctly maintained, Bora One hubs can deliver near-Ultra performance at a more accessible cost, making proper bearing adjustment a critical part of achieving top-tier rolling efficiency.
Conclusion
A rough-feeling Campagnolo Bora One hub is nearly always a sign of incorrect preload or contaminated bearings. Through careful adjustment, proper cleaning, and correct lubrication, the hub’s signature smoothness can be fully restored. Regular maintenance and minor adjustments, performed with precision, will keep your Bora One hubs spinning effortlessly for thousands of kilometers.