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

The SRAM RED Rear Derailleur [paid link] is a high-performance component designed for precision shifting and maximum efficiency. Whether you’re installing a brand-new derailleur, fine-tuning your shifting, or performing routine maintenance, this guide covers everything you need to know.

Tools Required [paid links]

Before you start, gather the following tools:


Step-by-Step Installation Guide

Proper installation of the SRAM RED Rear Derailleur [paid link] ensures smooth and responsive shifting. Follow these steps carefully:

1. Preparing Your Bike

Before installing the derailleur, make sure your bike is stable on a workstand. Remove the rear wheel and inspect the derailleur hanger for alignment. A misaligned hanger can cause shifting issues.

2. Attaching the Rear Derailleur

  • Thread the derailleur onto the derailleur hanger using a 5mm hex key [paid link].
  • Tighten the bolt to 8-10Nm using a torque wrench [paid link].
  • Ensure the derailleur is properly seated and does not wobble.

3. Installing the Chain

  • If you are using a new chain, measure and cut it to the correct length. SRAM recommends using the “big-big method” (largest chainring and largest cassette cog with no derailleur tension).
  • Thread the chain through the derailleur pulleys, ensuring proper routing.
  • Use a chain breaker tool to connect the chain with a PowerLock link.

4. Connecting the Shifter Cable (Mechanical Version)

For mechanical versions of the SRAM RED Rear Derailleur [paid link]:

  • Shift to the smallest rear cog before inserting the cable.
  • Feed the cable through the derailleur’s barrel adjuster and clamp bolt.
  • Tighten the cable bolt to 5-7Nm and trim excess cable.

For SRAM eTap AXS versions, pair the derailleur wirelessly following SRAM’s official pairing procedure.


Adjusting the SRAM RED Rear Derailleur

1. Setting the High and Low Limit Screws

  • Shift into the smallest cassette cog. Adjust the high-limit screw so the jockey wheel aligns directly under the cog.
  • Shift into the largest cassette cog. Adjust the low-limit screw to prevent the chain from overshifting into the spokes.

2. B-Gap Adjustment

  • The B-tension screw controls the distance between the upper pulley and the cassette.
  • Use SRAM’s recommended gap settings for your specific cassette size. Generally, 5-8mm of clearance is optimal for 12-speed drivetrains.

3. Fine-Tuning Indexing

  • Shift through all gears to check alignment.
  • Use the barrel adjuster to make small tuning adjustments. Turning counterclockwise increases cable tension, improving upshifts. Clockwise reduces tension for better downshifts.

Routine Maintenance for Longevity

1. Cleaning and Lubrication

  • Use a degreaser to remove built-up grime from the jockey wheels and chain.
  • Apply a dry or wet lubricant depending on riding conditions.
  • Wipe off excess lube to prevent dirt accumulation.

2. Checking for Wear and Tear

  • Inspect the jockey wheels for excessive wear. Replace them if the teeth appear sharp or uneven.
  • Check the derailleur cage for alignment issues. A bent cage can severely affect shifting performance.

Troubleshooting Common Issues

1. Slow or Inconsistent Shifting

  • Ensure the derailleur hanger is straight. Use a hanger alignment tool to correct any misalignment.
  • Check if the cable tension is too loose or tight. Adjust via the barrel adjuster.

2. Chain Skipping or Ghost Shifting

  • Ensure the cassette and chain are not excessively worn. A stretched chain can cause shifting inconsistencies.
  • Make sure the derailleur pulleys are clean and rotating freely.

3. Loud or Noisy Drivetrain

  • Check chain lubrication and remove any built-up dirt.
  • Make sure the chain is not too long, as excessive slack can cause noise.

Final Thoughts

A well-installed and properly adjusted SRAM RED Rear Derailleur ensures smooth, precise shifting. By following this guide, you can maintain optimal performance and extend the lifespan of your drivetrain. Regular maintenance, proper adjustments, and timely part replacements will keep your shifting crisp for years to come.