How to Adjust Rear Derailleur

A properly adjusted rear derailleur ensures smooth and responsive gear shifts. This guide will walk you through the steps to adjust the rear derailleur on your bike.

Tools Needed

• Bicycle stand (optional)
• Phillips screwdriver
• 5mm Allen wrench
• Needle-nose pliers
• Bike chain lubricant

Preparation

Place your bike on a stable surface or use a bike stand. Ensure the rear wheel is off the ground for easy spinning. Check your drivetrain components for wear and tear. Replace any worn components before you start the adjustments.

Check your Derailleur Hanger

Ensure the derailleur hanger is straight. A bent hanger can cause shifting problems. Use an alignment tool to correct any misalignment or take it to a bike shop if you lack the tool.

Set High and Low Limit Screws

The limit screws prevent your chain from derailing. They are typically marked with H for high gear and L for low gear.

Adjust the High Limit Screw

1. Shift your chain to the smallest cog.
2. Locate the H screw on the derailleur body.
3. Turn the screw until the jockey wheel aligns perfectly with the smallest cog.

Adjust the Low Limit Screw

1. Shift your chain to the largest cog.
2. Locate the L screw on the derailleur body.
3. Turn the screw until the jockey wheel aligns perfectly with the largest cog.

Adjust Cable Tension

Proper cable tension ensures accurate shifting between gears.

1. Shift to the smallest cog.
2. Use the barrel adjuster to fine-tune the cable tension. Turning it clockwise loosens the tension, while counterclockwise tightens it.
3. Shift through the gears to check for smooth transitions. Adjust until shifts are precise.

Indexing Adjustment

Indexing adjusts the shifter so each click moves the chain precisely one cog.

1. Shift to the second smallest cog.
2. Adjust the barrel adjuster to ensure the derailleur moves the chain smoothly to the next cog with each click of the shifter.
3. Test by shifting through all the gears.
4. Make minor adjustments as needed.

B-Tension Adjustment

This screw controls the derailleur’s distance from the cassette. Proper adjustment prevents the derailleur from hitting the larger cogs.

1. Locate the B-tension screw.
2. Shift to the largest cog.
3. Turn the B-tension screw until there is a 5-6mm gap between the upper jockey wheel and the largest cog.

Inspect and Lubricate the Chain

A clean and lubricated chain enhances shifting performance.

1. Clean the chain with a degreaser.
2. Apply lubricant evenly across all chain links.
3. Wipe off any excess lubricant with a clean cloth.

Final Checks

Test ride your bike to ensure all adjustments are correct. Shift through all gears and listen for any unusual noise. Make minor adjustments as needed. Keep your drivetrain clean and well-maintained for optimal performance.