How to Install, Adjust, and Maintain the SRAM NX Rear Derailleur

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in Rear Derailleur, SRAM

The SRAM NX Rear Derailleur [paid link] is a critical component in SRAM’s Eagle 1x drivetrain system, designed for mountain and trail riders who demand reliable, precise shifting at an affordable price point. Whether you’re installing a new derailleur, fine-tuning shifting performance, or performing regular maintenance, a proper setup is essential for smooth operation and drivetrain longevity.

In this guide, we’ll cover every aspect of the SRAM NX Rear Derailleur [paid link], including installation, adjustment, troubleshooting, and maintenance best practices. Follow these expert instructions to ensure your derailleur functions optimally on every ride.

Tools Required

  • 5mm Allen key
  • Torque wrench [paid link] (recommended)
  • Phillips screwdriver
  • Chain breaker tool
  • SRAM Eagle-compatible chain
  • Lubricant and degreaser
  • Rag or shop towel

Step-by-Step Installation of the SRAM NX Rear Derailleur

1. Preparing the Bike for Installation

Before installing your SRAM NX Rear Derailleur [paid link], shift your chain onto the smallest rear cog and remove the old derailleur if necessary. Inspect the derailleur hanger to ensure it is straight and free from damage. A misaligned hanger can cause poor shifting performance.

2. Mounting the Derailleur to the Hanger

  • Align the SRAM NX derailleur’s B-knuckle with the derailleur hanger.
  • Insert the mounting bolt into the hanger and tighten it using a 5mm Allen key.
  • Use a torque wrench [paid link] to secure the derailleur to the specified 8-10Nm torque. Over-tightening can damage the hanger, while under-tightening may lead to poor shifting.

3. Installing the Chain

  • Use a SRAM Eagle-compatible chain that matches your cassette range.
  • Wrap the chain around the cassette and derailleur, ensuring correct routing through the jockey wheels.
  • Use a chain breaker tool to set the chain to the correct length following SRAM’s recommended method.
  • Secure the chain using a SRAM PowerLock link and confirm it moves smoothly through the derailleur.

4. Attaching the Shifter Cable

  • Thread the shifter cable through the housing and into the derailleur’s cable anchor bolt.
  • Pull the cable taut and fasten the anchor bolt with a 5mm Allen key.
  • Trim excess cable and cap the end to prevent fraying.

Adjusting the SRAM NX Rear Derailleur for Optimal Shifting

1. Setting the High and Low Limit Screws

  • High Limit Screw (H-screw):
    • Shift to the smallest cog.
    • Adjust the H-screw to align the upper jockey wheel directly beneath the smallest cog.
  • Low Limit Screw (L-screw):
    • Shift to the largest cog.
    • Adjust the L-screw to ensure the derailleur does not overshoot the cassette.

2. Adjusting the B-Gap

The B-gap adjustment determines how the derailleur interacts with the cassette. SRAM recommends using their B-gap gauge for precise setup.

  • Shift to the largest cog.
  • Adjust the B-screw until the upper jockey wheel maintains a 14-16mm gap from the cog.
  • If shifting feels sluggish, increase the gap slightly.

3. Indexing the Gears

  • Shift to the second smallest cog and check alignment.
  • If shifting is slow, turn the barrel adjuster counterclockwise to increase tension.
  • If shifting is jumpy, turn the barrel adjuster clockwise to reduce tension.
  • Repeat until shifting is crisp and precise across all gears.

Maintaining Your SRAM NX Rear Derailleur

1. Cleaning and Lubrication

  • Regularly clean the derailleur with a degreaser and a soft brush to remove dirt and grime.
  • Wipe off excess degreaser and apply a light lubricant to the pulley wheels and pivot points.

2. Checking for Wear and Damage

  • Inspect the derailleur hanger for bends or cracks.
  • Check jockey wheels for excessive wear and replace if necessary.
  • Ensure the derailleur cage is not bent or misaligned.

3. Replacing the Cable and Housing

  • Over time, shifter cables stretch and housings become contaminated.
  • If shifting feels inconsistent, replace the cable and housing for a smoother experience.

Troubleshooting Common SRAM NX Rear Derailleur Issues

1. Slow or Inconsistent Shifting

  • Cause: Cable tension too loose or tight.
  • Solution: Adjust the barrel adjuster to fine-tune tension.

2. Chain Skipping or Jumping

  • Cause: Worn cassette, chain, or derailleur jockey wheels.
  • Solution: Inspect components and replace worn parts.

3. Grinding Noises During Shifting

  • Cause: Dirty or dry jockey wheels.
  • Solution: Clean and lubricate the derailleur.

SRAM NX Rear Derailleur vs. Other Models

Compared to the SRAM GX Eagle Rear Derailleur [paid link], the NX model offers:

  • Heavier construction (steel cage vs. aluminum)
  • Less refined clutch mechanism, making chain retention slightly less smooth
  • More affordable price point, making it a great choice for budget-conscious riders

Conclusion

The SRAM NX Rear Derailleur is a reliable and cost-effective option for riders looking to experience the benefits of SRAM’s Eagle drivetrain. With proper installation, adjustment, and maintenance, this derailleur provides smooth shifting performance and long-term durability.

Regular cleaning, proper cable tensioning, and correct B-gap adjustments are essential for optimal function. By following this guide, you can ensure your SRAM NX Rear Derailleur delivers precise, hassle-free shifting on every ride.