The SR Suntour TriAir2 [paid link] rear shock is a high-performance suspension component designed to provide excellent damping and support for mountain and gravel bikes. Whether you’re looking to install, maintain, or troubleshoot your TriAir2 [paid link], this guide will walk you through the essential steps for servicing this rear shock, ensuring it operates optimally for long periods. By understanding the proper techniques for installation, adjustment, and troubleshooting, you can maximize the performance and lifespan of your TriAir2 rear shock.

Tools Required

To properly service your SR Suntour TriAir2 rear shock, ensure you have the following tools at hand:

• Shock pump (compatible with TriAir2 shock)
• Torque wrench [paid link] (capable of 2-10 Nm torque range)
• 5mm, 6mm, and 8mm hex wrenches
• T25 Torx wrench [paid link]
• 17mm open-end wrench (for air valve)
• A clean rag
• Shock oil (per SR Suntour’s recommendations)
• Suspension grease
• Oil drain pan or container
• Rags for cleaning
• Latex gloves (optional but recommended for cleanliness)

Installation of the TriAir2 Rear Shock

Step-by-Step Installation Process

1. Preparation: Clean the area where the shock will be installed to prevent dirt and debris from entering the shock’s internals. Ensure your bike’s rear triangle is free of grease and other lubricants.
2. Position the Shock: The TriAir2 rear shock should be aligned correctly with the frame’s mounting points. It’s essential that the eyelet mount of the shock matches the bike frame’s shock mount. Ensure the shock is positioned to allow easy access to the air valve and adjusters.
3. Secure the Shock: Using your 5mm or 6mm hex wrenches, tighten the mounting bolts at both ends of the shock. Be sure not to overtighten; use a torque wrench [paid link] to tighten them to the recommended torque settings (typically between 2 to 6 Nm). This ensures the shock is secure and avoids stressing the mounting points.
4. Set Up the Air Pressure: Attach your shock pump to the air valve on the TriAir2 rear shock. Set the air pressure according to your rider weight and suspension setup preferences. Adjustments can vary depending on your weight, riding style, and terrain.
5. Final Check: Before finishing, double-check that the shock is securely mounted and that the air pressure is properly set. Also, confirm that the rebound and compression adjustments are within their recommended ranges for your ride style.

Adjusting the TriAir2 Rear Shock

Setting Air Pressure

The air pressure in the TriAir2 rear shock directly affects your bike’s overall suspension feel. It’s crucial to match the air pressure to your body weight and preferred riding style. For cross-country and lightweight riders, you may prefer a higher air pressure for firmer support. For enduro or downhill riders, lower air pressures may be ideal for added plushness.

• Set initial air pressure: Start by setting the shock pressure at 200-220 psi for riders around 70-80 kg.
• Fine-tune: After your first ride, adjust the pressure based on your experience. If you find the shock too stiff, lower the pressure slightly. If it’s bottoming out too often, raise the pressure to prevent excessive travel.

Adjusting Rebound and Compression

The TriAir2 features both rebound and compression adjustments, allowing you to tailor the shock’s performance to your needs.

• Rebound Adjustment: Adjust the rebound speed to control how quickly the shock returns after compression. Turn the rebound knob clockwise to slow down the rebound and counterclockwise to speed it up. Typically, 10 clicks from fully closed is a good starting point.
• Compression Adjustment: Compression controls the shock’s resistance to impacts and how quickly the shock compresses. Turn the compression dial to adjust the amount of resistance. For smoother terrain, a softer compression setting is best, while for aggressive or technical riding, a firmer compression might provide more control.

Maintenance of the TriAir2 Rear Shock

Regular Maintenance Intervals

For longevity and optimal performance, regular maintenance is necessary. This includes checking the air pressure, cleaning the shock body, and performing oil changes as recommended by SR Suntour.

• Monthly: Clean the shock body to prevent dirt buildup. Use a clean rag to wipe away dirt, especially around the seals.
• Every 50 hours of riding: Perform a basic oil change. This will involve draining the shock and replacing the suspension fluid, which ensures smooth performance and proper damping.
• Every 100 hours of riding: A more thorough inspection and servicing, including seal replacements and internal cleaning, may be needed.

How to Drain and Refill Oil

1. Remove the shock from the bike.
2. Use a T25 Torx wrench [paid link] to remove the oil drain screw.
3. Let the shock oil fully drain into an oil container.
4. Refill the shock with the recommended oil type. Be sure to follow SR Suntour’s specifications for oil volume and type.
5. Replace the drain screw, making sure it is tightened to the proper torque.

Seals and Lubrication

The seals on the TriAir2 are crucial for keeping debris and moisture out while maintaining consistent damping performance. Regularly inspect the seals for wear or damage. Use suspension grease to lubricate the seals lightly during maintenance to ensure smooth movement.

Troubleshooting Common Issues

Issue 1: Lack of Rebound Control

If the shock feels overly stiff and doesn’t rebound smoothly, the issue may lie in the rebound setting or an under-filled oil chamber. Check and adjust the rebound dial first, and if that doesn’t resolve the issue, consider performing an oil change.

Issue 2: Bottoming Out

If the shock is bottoming out too frequently, the air pressure is likely too low. Increase the pressure incrementally until you reach the ideal balance. Also, check that your compression settings are not too soft.

Issue 3: Noisy Shock

A noisy shock is usually a sign of inadequate lubrication or dirt within the shock. Clean and lubricate the shock regularly. If the noise persists, check for worn seals or internal components that might need replacing.

Customization and Performance Optimization

Adjusting for Terrain and Riding Style

The TriAir2 rear shock is designed with adjustability in mind, allowing riders to customize their setup for various types of terrain and riding styles.

• For Cross-Country (XC): Opt for higher air pressures and stiffer compression settings to minimize suspension movement and maintain efficient pedaling.
• For Enduro/Downhill: Set a lower air pressure for a more plush ride, with a firmer compression setting to handle aggressive impacts and rough terrain.

Upgrading the Shock

If you’re looking to optimize performance further, consider upgrading the shock’s internals or switching to a higher-quality shock oil. Advanced riders often opt for custom tuning to suit their specific riding needs.

Compatibility with Other Drivetrain Components

The TriAir2 rear shock is highly compatible with most modern mountain bike frames, particularly those designed for aggressive trail, enduro, or cross-country riding. However, ensure that your frame’s shock mounts and linkage are compatible with the shock’s eyelet dimensions. Always consult your frame manufacturer’s guidelines to ensure compatibility with your current drivetrain and rear triangle setup.

The shock’s performance will also depend on how it pairs with your overall suspension system. For example, pairing it with a compatible front fork like the SR Suntour Aion or XCR will offer balanced suspension performance for trail riders.

Conclusion

Proper servicing and maintenance of your SR Suntour TriAir2 rear shock are essential for its long-term performance and reliability. By following the installation, adjustment, and troubleshooting steps outlined in this guide, you can ensure that your rear shock performs at its best on every ride. Regular maintenance, oil changes, and seal inspections will help keep your shock in top condition, while understanding how to adjust its settings will allow you to tailor it to your specific riding style and terrain.