Adjust Sag

Sag is the amount your suspension compresses under your weight when you sit on the bike in your riding position. It's typically measured as a percentage of the total travel.

1. Measure Total Travel: Determine the total travel of your fork and rear shock.

2. Set Initial Pressure:

   • For air forks/shocks, use a shock pump to set the air pressure.
   • For coil springs, select a spring rate that matches your weight.

3. Check Sag:

   • Sit on the bike in your riding position with your feet on the pedals. You can have a friend help, or use a wall for balance.
   • Measure the distance the bike compresses from full extension to the current position. Subtract this measurement from the total travel to calculate sag.

4. Target Sag Percentage:

   • Cross-country (XC): 20-25%
   • Trail/All-Mountain: 25-30%
   • Enduro: 30-35%
   • Downhill: 30-40%

5. Adjust Pressure: If your sag is too low or too high, adjust the air pressure or change the coil spring until you achieve the desired percentage.

Step 4: Set Rebound and Compression

After setting the sag, focus on tuning the rebound and compression settings for both your fork and shock.

Rebound

• Purpose: Controls how fast your suspension returns to its original position after compression.
• Adjustment:
  • Turn the rebound knob (usually labeled with a rabbit/tortoise symbol).
  • Faster Rebound (rabbit): Returns quickly, suitable for smooth terrain.
  • Slower Rebound (tortoise): Returns slowly, better for rough terrain.
• Test Ride: Make small adjustments and take test rides, focusing on how the bike feels on different terrains.

Compression

• Purpose: Controls how your suspension compresses under weight and impacts.
• Adjustment:
  • There are often separate adjustments for high-speed and low-speed compression.
  • Low-Speed Compression: Affects how the suspension reacts to slow inputs (pedaling, braking).
  • High-Speed Compression: Affects how the suspension reacts to fast hits (rocky terrain, jumps).
• Test Ride: Adjust and test ride to find a balance that prevents bottoming out without feeling harsh.

Step 5: Fine-Tune Settings

After initial adjustments, take your bike out on the trails to test the settings. Pay attention to how the bike feels on various terrains:

• If you feel like you’re bottoming out too much, consider increasing compression settings or adding more air (or a stiffer spring).
• If the bike feels bouncy or is too harsh, consider reducing compression or decreasing air pressure (or a softer spring).

Step 6: Record Settings

Once you find a setup you like, record your settings for future reference. If you make changes, you’ll have a baseline to compare against.

Step 7: Regular Maintenance

• Check Pressure: Regularly check air pressure in your fork and shock as it can fluctuate with temperature and riding conditions.
• Inspect Seals: Make sure to inspect and maintain the seals and oil in your suspension regularly, as proper maintenance is key to performance.

Conclusion

Tuning your bike's suspension is a vital part of optimizing your riding experience. By understanding your weight, setting sag, and adjusting rebound and compression, you can create a setup that enhances comfort and performance on the trails. Remember, tuning is a personal process—what works for one rider may not work for another. Don’t hesitate to experiment with different settings until you find what feels best for your riding style!