1. Product Overview
The RUJIXU 690S SLR I9 690 rings Bicycle MTB Hub is a high-performance component designed for mountain bikes. It features sealed bearings for smooth rotation and durability, a 6-bolt disc brake interface, and a J-bend spoke design. This hub is available in various configurations to suit different axle standards and cassette types (HG, XD, MS).
2. Specifications
| Feature | Description |
|---|---|
| Brand Name | RUJIXU |
| Model Number | 690S |
| Category | Bearing Hub |
| Braking System | Disc Brake (6-bolt) |
| Hub Hole Number | 32 Holes |
| Bearings | Front: 2 Sealed Bearings, Rear: 4 Sealed Bearings |
| Freehub Body Material | 7075 Aluminum Alloy |
| Freehub Engagement | 690 rings |
| Cassette Compatibility | Shimano HG 8-12 speed, SRAM NX SX 12-speed (upgradeable to XD/MS) |
| Front Hub Spacing | 100x9mm (QR), 100x15mm (TA), 110x15mm (TA) |
| Rear Hub Spacing | 135x10mm (QR), 142x12mm (TA), 148x12mm (TA) |
| Weight (Approx.) | Front: 150g, Rear: 270g (Total: 420g) |
| Origin | Mainland China |
| Package Dimensions | Length: 23cm, Width: 15cm, Height: 15cm |
| Package Weight | 1.0 kg |
3. Package Contents
Upon opening the package, please ensure all components are present and undamaged:
- 1 x RUJIXU 690S Front Hub
- 1 x RUJIXU 690S Rear Hub
- Appropriate end caps and adapters for selected axle standard (QR or TA)
- Freehub body (HG, XD, or MS, depending on selection)
4. Installation
Proper installation is crucial for the performance and longevity of your hubs. If you are unsure about any steps, it is highly recommended to seek assistance from a qualified bicycle mechanic.
4.1. Compatibility Check
- Ensure the selected hub spacing (e.g., Front 100x9mm, Rear 142x12mm) matches your bicycle frame and fork.
- Verify that the freehub body type (HG, XD, or MS) is compatible with your cassette.
- Confirm that your disc brake rotors are 6-bolt compatible.
- The hubs are designed for 32-hole rims. Ensure your rims have 32 spoke holes.
4.2. Wheel Building
The hubs must be laced into a wheel rim using spokes. This process requires specialized tools and knowledge to ensure correct spoke tension and wheel trueness. It is strongly advised to have a professional wheel builder assemble your wheels.
- Select appropriate J-bend spokes and nipples.
- Lace the spokes according to your desired lacing pattern.
- Tension and true the wheel to manufacturer specifications.
4.3. Freehub Body and Cassette Installation
- Ensure the freehub body is securely attached to the rear hub. The video below demonstrates the internal pawl mechanism of the freehub body.
- Slide your cassette onto the freehub body, aligning the splines.
- Install the cassette lockring and tighten it to the manufacturer's specified torque using a cassette tool and torque wrench.
4.4. Disc Rotor Installation
- Attach your 6-bolt disc brake rotors to the hub flanges using the appropriate bolts.
- Tighten the bolts in a star pattern to the manufacturer's specified torque.
4.5. Axle Installation
Install the wheels onto your bicycle, ensuring the quick release (QR) skewers or thru-axles (TA) are correctly seated and tightened according to your bike manufacturer's recommendations.
5. Operation
Once installed, the RUJIXU 690S hubs provide a reliable and smooth rolling experience. The sealed bearings minimize friction, and the 690-ring freehub mechanism ensures quick and positive engagement when pedaling. The 6-bolt disc brake interface provides secure mounting for your braking system.
6. Maintenance
Regular maintenance will extend the life and performance of your hubs.
- Cleaning: Keep the hubs clean from dirt, mud, and grime. Use a soft cloth and mild detergent if necessary. Avoid high-pressure washing directly on the hub seals.
- Inspection: Periodically check for any signs of wear, damage, or loose components. Ensure all bolts (disc rotor, axle) are tightened to their correct torque specifications.
- Bearing Check: While sealed bearings require less maintenance, occasionally check for excessive play or roughness by spinning the wheel and gently wiggling the axle. If issues are detected, professional servicing or bearing replacement may be required.
- Freehub Body: The freehub body's pawls and springs should be inspected and lightly lubricated with a thin, non-migrating grease or freehub-specific oil if any issues with engagement or excessive noise (beyond the normal 690-ring sound) occur. This is a delicate procedure and should ideally be performed by a professional.
7. Troubleshooting
Here are some common issues and potential solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| Excessive play in wheel | Loose axle, worn bearings | Check axle tightness. Inspect and replace bearings if worn. |
| Unusual noise (grinding, squealing) | Contaminated or worn bearings, dry freehub pawls | Clean and lubricate freehub pawls. Replace bearings if necessary. |
| Freehub not engaging or slipping | Dirty/damaged pawls or springs, worn freehub body | Inspect and clean freehub pawls. Replace freehub body if worn. |
| Disc brake rubbing | Improperly installed rotor, bent rotor, misaligned caliper | Re-install rotor, true rotor, adjust brake caliper. |
For any complex issues or repairs, consult a professional bicycle mechanic.
8. User Tips
- Axle Standards: Be aware that 148x12mm is a common rear hub standard, often referred to as "Boost" spacing. Always confirm your frame's requirements.
- Spoke Length: When building wheels, spoke length is critical and depends on your rim's Effective Rim Diameter (ERD) and the hub's flange diameters. Always use a spoke length calculator or consult a professional wheel builder to determine the correct spoke lengths for your specific setup.
- Freehub Noise: The 690-ring engagement system is designed for quick response and may produce a distinct, louder freehub sound compared to other hub designs. This is normal operation.
- Compatibility: This hub is designed for 32-hole rims. If you require a different spoke count (e.g., 28 holes), this specific model will not be compatible.
9. Warranty and Support
For warranty claims, technical support, or any questions regarding your RUJIXU 690S hubs, please contact the seller or manufacturer directly. Keep your proof of purchase for any warranty-related inquiries.
