What is the lifespan of a ball bearing?

Factors Determining Ball Bearing Lifespan

1. Lubrication Condition Determines Lifespan
Grease Degradation: High temperatures or moisture intrusion cause grease decomposition (resulting in dryness, caking, or a sour odor) → Direct metal-to-metal friction → Lifespan shortened by over 80%
Seal Failure: Cracks in rubber oil seals allow sand and mud to enter the grease, forming abrasive slurry → Accelerated raceway wear

2. Load Intensity Directly Shortens Lifespan
Overload Indentation: Overload or strong impacts leave permanent indentations in the raceways → Continuous vibration and noise during operation
Uneven Load Wear: Improper Shaft Installation Leads to Stress Concentration → Premature Spalling of One-Side Raceways

3. External Environment Accelerates Degradation
Water Erosion and Rust Penetration: Unmaintained after riding in the rain, moisture penetration causes rusting of the raceways → Spalling and pitting
Dust Intrusion: Sand in off-road environments penetrates, scratching the raceway surface (visible brushed lines)

4. Installation Techniques Can Harm Hidden Dangers
Rough Disassembly: Hammering during installation causes minor deformation → Premature bearing noise.
Preload errors: Overtightening causes heat and sintering, while over-loosening causes shaking and impact.

5. Widening gaps in quality grades.
Material purity: Inferior bearing steel contains impurities → premature fatigue cracking.
Heat treatment: Inadequate surface hardening → pitting and flaking (feeling uneven with a finger).

6. Maintenance habits are key to extending bearing life.
Regular greasing: Refill with high-temperature lithium-based grease every 5,000 kilometers (old oil turns black and needs to be cleaned).
Flushing taboos: Using a high-pressure water jet directly on the bearing can cause the seal lip to flip.