DNM Bicycle Air Shock Absorber User Manual

Introduction to DNM Air Shocks

Congratulations on purchasing the best suspension shock absorber for Mountain Bike Technology. DNM shocks are crafted from lightweight, high-strength materials, designed for high performance, ease of use, and simple maintenance. This manual contains crucial information regarding safe installation, proper operation, and maintenance of your product. Please read it carefully and follow the recommendations to ensure an enjoyable and trouble-free mountain biking experience.

Symbol Description: ❗ Warning, ⚠️ Attention

Installation of a New Shock

When upgrading your rear shock, the most important step is to ensure you have the correct unit for your specific application. Determine your primary riding style (e.g., Downhill, Cross Country, Free Riding, or Road). Upgrading your shock can significantly alter your bike's handling and performance on varied terrain. Selecting the appropriate shock is crucial; for instance, installing a lightweight air shock on a downhill bike or a long-travel shock on a lightweight dual suspension bike would be unsuitable.

1. Measure Shock Length: Establish the required shock length by measuring from eyelet to eyelet. Use calipers or a metal ruler for accuracy. The correct length is the distance from the center of the bolt at the head of the shock to the center of the other bolt at the base.
2. Measure Aluminum Sleeve Width: Determine the width of the aluminum sleeves at both ends of the shock, which pass through the bushings and connect the shock to the frame and swing arm. Use calipers to measure from the inside of the mount on both sides. The shock mounting gap should match the aluminum sleeve. Consult a professional bike shop if your bike has a different setup.
3. Check Clearance for Extended Travel: If you plan to extend your bike's travel, ensure sufficient clearance for the full travel of the rear swing arm. If using a shock with an external reservoir (piggyback chamber), verify it fits your frame and moves smoothly without interfering with the frame or seat posts.
4. Clean Mounting Area: Once you have the correct shock length and bushing gap, remove the old shock absorber. Clean the frame and swing arm's inside surfaces thoroughly to remove dirt.
5. Positioning the Shock: Consider the adjuster's position when deciding the shock's orientation. Use a 5mm Allen key and a 10mm open-ended spanner for mounting, or other suitable tools depending on your fastener type.
6. Tightening Process: Apply medium pressure. Aluminum spacers are tolerance fit. Use Nylock nuts or Loctite fastening solution. After installation, gently sit on the bike and progressively apply more pressure, easing the bike through its travel. If no strange noises come from the shock area, the installation is likely successful.
7. Final Adjustments: Fine-tune your setup. Use the collar on the main shock body to adjust ride height by compressing the spring. The rebound adjuster controls the shock's rebound speed. The compression damper fine-tunes the stroke. These adjustments are variable and may need periodic changes based on riding conditions.
8. Ready to Ride: With your helmet on, you are now ready to enjoy your ride with a well-equipped and adjusted bike.

Shock Information

1. Compressing Damping: Resistance felt when compressing the shock.
2. Rebound Damping: Controls the shock's rebound speed.
3. Preload: Initial static force applied to the spring.
4. Spring Rate: Force required to compress the spring.
5. Shock Sag: The amount the shock compresses under the rider's weight in a normal riding position. Recommended sag is 15%-25% for cross-country and 25% for Downhill applications.
6. Lock-Out: A unique DNM feature allowing riders to choose different riding styles. Locking the shock movement reduces suspension travel, making hill climbs easier and enabling faster acceleration (depending on track conditions). Available in remote and manual lock-out systems.
7. Remote Lock-Out: Allows operation of the lock-out system from the handlebars via a thumb shifter.

DNM AO-38RC Adjustments

This section describes specific adjustments for the AO-38RC model.

Rebound Adjustment (Red Knob)

Turn towards '+': Increases damping (slower rebound). Turn towards '-': Decreases damping (faster rebound).

Compression Adjustment (Blue Knob)

Turn towards '+': Locks out the shock. Turn towards '-': Opens the shock.

Positive Pressure Valve

Add compressed air according to the recommended pressure table.

AO-38RC Specification Table

SAG Set-up Instructions

To achieve maximum performance from your DNM shock in any situation, SAG adjustment is essential. SAG variation primarily depends on weight (bike or rider). When setting SAG, sit properly on the saddle, ensuring all your weight is on the bike. Observe the ring position on the shock travel body after dismounting. A displacement percentage range of 15%~25% of full travel is suggested. Increasing air pressure will decrease displacement, while decreasing it will increase displacement. Adjust air pressure to achieve your desired SAG.

Air Shocks Overview

DNM Air Shocks are high-quality air hydraulic shocks featuring a hard-anodized shaft and black shock body. Adjustments include Compression, Rebound, Negative Air Spring, and Lock-Out.

• The Compression air valve is located near the rebound adjuster and the blue lock-out knob. Factory-filled with 150psi. Increasing air pressure makes the shock harder; decreasing it makes it softer.
• Negative air pressure is factory-filled with 50psi and should be adjusted between 50psi~80psi.
• The Rebound adjuster (red circular knob) is located between the main air valve adjuster and the blue lock-out knob. Turning it controls the shock's speed (slower or faster).
• Lock-out adjustment (blue knob) locks the shock's movement and reduces rear suspension travel. Pull the knob to activate the lock-out feature, press it in to turn it off.

Adjusting SAG is crucial for optimal DNM shock performance. Refer to the Shock Specification Table and Set-Up Instructions.

Air Pressure Recommendation Table (Main Air Chamber & Negative Air Chamber)

Note: These numbers are for reference only. Air pressure depends on rider's weight and frame specification. For more information, visit www.dnmshock.com.

Service and Maintenance

1. Do not disassemble the shock yourself. Contact your nearest DNM authorized service center for malfunctions or improper operation. The internal air is nitrogen-filled. Disassembly by unauthorized personnel will void responsibility for any issues.
2. Air Pressure Limits: DNM shocks are filled with high-pressure air (150psi) during production. Maximum air pressure is 250psi. Negative air room pressure is 50psi, maximum 80psi.
3. Bearing Sleeve Maintenance: After approximately 5000km of riding, remove, clean, grease, and replace the mount bearing sleeves from both sides if necessary.
4. Post-Ride Cleaning: After muddy rides, clean the main shaft, dust seal, and bumper rubber to protect the shock and extend its lifespan. Wash your shock only with soap and water; never use high-pressure washers.
5. Pre-Ride Adjustment: Check and adjust the main air spring pressure and negative air spring pressure to your desired level before riding.
6. Adjustment Note: If you need to adjust your shock harder or softer, always adjust the air pressure.

Terms and Conditions / Limited Warranty

• DNM warrants its fork or shock for one year from the date of purchase to the original purchaser. This warranty does not extend to third parties.
• Warranty covers defects in materials and workmanship. All forks must be returned to DNM for inspection. If found defective, DNM will replace or repair them. DNM is not liable for indirect, special, or consequential damages.
• Warranty does not apply to products improperly installed or adjusted, misused, or those with missing or altered serial numbers.
• Warranty does not cover damage to appearance or normal wear and tear from bicycle use.
• For warranty claims, contact the dealer or a DNM service center. A copy of the proof of purchase must be included.
• If a product needs replacement and is discontinued or unavailable, DNM reserves the right to replace it with one of equal value. No refunds are provided.

Disclaimer

DNM is not responsible for any damages to you or others arising from riding, transporting, or any other use of your shock or bicycle. In case your shock breaks or malfunctions, DNM's liability is limited to the repair or replacement of your shock, according to the terms and conditions outlined in this manual's Service and Warranty section.