1. Introduction
The DNM AO-39RC is a high-performance pneumatic shock absorber designed for mountain bikes, suitable for various terrains including soft tail, speed drop, and off-road applications. It features a double air chamber structure, damping adjustment, and a three-stage locking system to provide optimal suspension performance and control.
2. Specifications
The DNM AO-39RC shock absorber is constructed from durable aluminum alloy, ensuring high strength and light weight. Key specifications are detailed below:
| Attribute | Description |
|---|---|
| Model Number | AO-39RC |
| Material | Aluminum/Alloy |
| Use | Mountain Bikes |
| Origin | Mainland China |
| Length Options | 165mm, 190mm, 200mm |
| Stroke Length | 35mm (for 165mm length), 50mm (for 190mm length), 55mm (for 200mm length) |
| Weight (including bushing) | 293g (165mm), 315g (190mm), 324g (200mm) |
| Max Air Pressure | Do not exceed 275psi. The air pressure in the auxiliary air chamber must not exceed the main air chamber. |
3. Package Contents
The package typically includes:
- DNM AO-39RC Pneumatic Shock Absorber (selected length)
- Bushing set (default delivery 24mm*2)
If you require a different length bushing (available sizes: M8*22/24/26/32/42/44/50/54/56mm), please ensure to specify this at the time of purchase.
4. Setup
4.1 Installation
Mount the shock absorber securely to your mountain bike's frame using appropriate hardware. Ensure all bolts are tightened to the manufacturer's recommended torque specifications for your bike frame.
4.2 Air Pressure Adjustment
The shock absorber features a double air chamber structure. Adjust the air pressure using a high-pressure shock pump (not included).
- The maximum air pressure should not exceed 275psi.
- The air pressure in the auxiliary air chamber must not exceed the air pressure in the main air chamber.
Proper air pressure is crucial for optimal performance and rider comfort. Refer to your bike's manual or a suspension setup guide for recommended pressure settings based on rider weight and riding style.
5. Operating Instructions
5.1 Three-Stage Locking System
The AO-39RC features a convenient lock switch to adapt to different riding conditions:
- Locked State: Suitable for smooth surfaces like highways, providing maximum pedaling efficiency.
- Half Locked State: Ideal for walking on rough roads and general off-road use, offering a balance of efficiency and comfort.
- Open State: Best for mild off-road use, providing full suspension travel for maximum bump absorption.
5.2 Damping Adjustment
The damping adjustment knob allows you to fine-tune the rebound speed of the shock absorber:
- Clockwise (S): Rotating the knob clockwise slows down the rebound speed. This is generally preferred for obstacles that are far apart and have large intensity, allowing the shock to recover slowly.
- Counterclockwise (F): Rotating the knob counterclockwise makes the rebound speed faster. This is suitable for barriers that are closer together and have smaller strength, allowing the shock to rebound quickly for successive impacts.
6. Maintenance
To ensure the longevity and optimal performance of your DNM AO-39RC shock absorber, regular maintenance is recommended:
- Clean Regularly: After each ride, especially in dirty or wet conditions, clean the shock absorber with mild soap and water. Avoid high-pressure washers directly on seals.
- Inspect for Damage: Periodically check for any signs of wear, cracks, or leaks on the body, seals, and bushings.
- Check Air Pressure: Verify air pressure before each ride and adjust as necessary to maintain desired performance.
- Bushing Inspection: Ensure bushings are free from excessive play or wear. Replace if necessary.
- Professional Service: For internal service or complex repairs, it is recommended to consult a professional bike mechanic or authorized service center.
7. Troubleshooting
This section provides basic troubleshooting steps for common issues. For more complex problems, please consult a professional bike mechanic.
7.1 Loss of Air Pressure
- Check Valve Cap: Ensure the valve cap is securely tightened.
- Inspect for Leaks: Apply soapy water around the air valve and seals to check for bubbles, indicating a leak.
- Re-inflate: Re-inflate to the correct pressure. If pressure loss persists, professional service may be required.
7.2 Poor Damping Performance
- Adjust Damping Knob: Experiment with the damping adjustment knob (Section 5.2) to find the optimal rebound speed for your riding style and terrain.
- Check Air Pressure: Incorrect air pressure can affect damping. Ensure it is set correctly.
7.3 Excessive Play/Noise
- Check Mounting Bolts: Ensure all mounting bolts are tightened to the correct torque.
- Inspect Bushings: Worn or damaged bushings can cause play. Inspect and replace if necessary.
8. User Tips
- Verify Dimensions: Before purchasing or installing, carefully measure the required length and stroke of your shock absorber to ensure compatibility with your bike frame. Pay attention to eyelet diameter and width.
- Personalize Settings: Take the time to experiment with both air pressure and damping adjustments to find the settings that best suit your weight, riding style, and the terrain you typically ride on. Small adjustments can make a big difference.
- Regular Cleaning: Keep the shock absorber clean, especially the shaft and seals, to prevent dirt and debris from causing premature wear.
9. Warranty & Support
For information regarding warranty coverage, claims, or technical support, please refer to the seller's specific policies or contact the retailer where the product was purchased. Keep your proof of purchase for any warranty-related inquiries.
