Setting up the correct rear shock sag for your Öhlins STX22 Coil is an essential step in optimizing your bike’s suspension performance. Sag refers to the amount the shock compresses under the rider’s weight and is crucial for achieving optimal ride quality. Proper sag ensures that your suspension works efficiently, providing better traction, control, and comfort on rough terrain. In this guide, we’ll walk through the steps required to properly set up the rear shock sag for the STX22 Coil, troubleshoot common issues, and explore ways to customize and optimize its performance.

Understanding Rear Shock Sag

Rear shock sag is an important parameter that directly affects the ride quality and handling of your bike. It’s the initial compression of the shock when you sit on the bike, and it’s typically measured as a percentage of the shock’s total travel. The correct amount of sag allows the suspension to remain active over rough terrain without bottoming out or feeling too stiff.

For the STX22 Coil shock, achieving the correct sag involves balancing your body weight, the shock’s spring rate, and the rebound settings. Proper sag setup can significantly improve your bike’s handling and make your ride more enjoyable, especially on challenging trails.

Tools Required

• Shock pump
• Ruler or sag measurement tool
• Allen wrenches [paid link] (for adjusting the shock)
• Tape measure (optional for precise measurement)
• Torque wrench [paid link] (optional for final tightening)

Step-by-Step Guide to Setting Up Sag on the STX22 Coil

1. Prepare the Bike and Rear Shock

• Place the bike on a flat surface and ensure the wheels are both off the ground.
• Adjust your saddle height and position to ensure your riding posture is correct.
• Double-check that your rear shock is properly mounted and securely attached to the frame.

2. Measure Your Rider Weight

• To ensure proper spring rate, it’s essential to know your body weight, as it plays a critical role in determining the amount of sag required. If you’re unsure about your spring choice, refer to Öhlins’ recommended spring rate chart or consult a bike shop.

3. Set the Initial Air Pressure

• If you haven’t already set the air pressure, use a shock pump to add the recommended starting pressure for the STX22 Coil.
• Most coil shocks don’t require air pressure but use a coil spring instead. Ensure the spring is appropriately matched to your weight and riding style.

4. Position Your Sag Measurement Tool

• With the shock pump and tools ready, mount the sag measurement tool (or use a zip tie around the shock shaft) just above the dust seal to mark the starting point.
• It’s important that the tool is positioned close enough to the shock to ensure an accurate measurement.

5. Settle Into Riding Position

• Put on your full riding gear (helmet, pads, etc.) and carefully get onto the bike. Keep both feet on the pedals in the riding position.
• Stand up slightly to engage your legs and then sit down, allowing your weight to compress the rear shock.

6. Take the Measurement

• With your weight fully on the bike, use the sag measurement tool or check the zip tie position to observe how much the shock compresses. Ideally, you should see about 30-35% of the shock’s total travel as sag for most riders.
• For example, if your shock has 100mm of travel, a sag of 30-35mm would be ideal.

7. Adjust the Coil Spring Preload

• If the sag is too low (too little compression), the shock may feel harsh, and you might need to reduce the preload by adjusting the spring collar.
• If the sag is too high (too much compression), the bike may bottom out easily, and you might need to increase the preload by tightening the spring collar.

8. Fine-Tune the Adjustment

• Make incremental adjustments and recheck the sag. Ensure you’re in the riding position each time you check. Even small changes in preload can make a noticeable difference in how the shock behaves.
• After fine-tuning, you should be able to achieve the correct sag without going beyond the recommended range.

Troubleshooting Common Set-Up Issues

While setting up your STX22 Coil rear shock, you may encounter common issues that can affect sag performance. Here’s how to troubleshoot them:

1. Sag Not Achieving the Recommended Range

• Issue: If you’re unable to reach the desired sag, even after adjusting the preload, it may indicate the wrong spring rate for your weight.
• Solution: Consider swapping out your current coil spring for a firmer or softer one, depending on whether you need more or less sag.

2. Bottoming Out During Ride

• Issue: If your shock bottoms out too easily, it’s a sign that your sag might be too deep.
• Solution: Increase the preload to reduce the sag, and ensure that your shock is operating within its optimal travel range.

3. Too Stiff or Harsh Ride

• Issue: If the ride feels too stiff, your sag may be too shallow, causing the shock to be overly compressed during bumps.
• Solution: Decrease the preload to allow the shock to compress more easily, giving it more responsiveness on rough terrain.

Customization and Optimization for Better Performance

The Öhlins STX22 Coil shock is highly customizable, allowing riders to adjust the shock’s damping and preload settings to fine-tune the suspension to their needs. Here are a few tips for optimizing performance:

• Rebound Adjustment: The STX22 Coil features an easy-to-use rebound adjustment dial. If your shock rebounds too quickly after compression, slow it down. If it rebounds too slowly, increase the rebound speed.
• Compression Damping: Experiment with the high and low-speed compression settings to adjust how the shock reacts to smaller or larger impacts. For smoother trails, lower compression settings may be ideal, while rougher terrains might benefit from firmer compression.
• Spring Rate Selection: The coil spring rate affects how much the shock compresses under load. Choose a spring rate based on your weight and the type of terrain you ride on.

Compatibility with Other Drivetrain Components

While the rear shock setup primarily affects suspension performance, it’s important to ensure compatibility with your bike’s other components. The STX22 Coil is designed to work with a wide range of mountain bikes but check the specifications of your frame and rear triangle to ensure proper fitment. When selecting a spring rate, always consider the overall weight distribution, including the drivetrain and wheels.

Conclusion

Setting up the rear shock sag on your Öhlins STX22 Coil is a critical part of ensuring that your suspension performs at its best. By following this detailed guide, you can achieve the ideal sag setup, troubleshoot any issues that arise, and make fine adjustments to suit your riding style. Proper sag and suspension setup not only improve comfort but also enhance your bike’s performance, allowing you to ride with more control and confidence.