The Shimano CS-6700 [paid link] cassette, part of the trusted Ultegra 6700 series, is engineered for precise road cycling performance. Despite its reliability, improper installation or setup can lead to subtle but frustrating drivetrain issues. This guide explores common reasons why your CS-6700 [paid link] cassette might not be performing as expected and how to correct each issue effectively.
Tools Required
- 10mm Allen wrench [paid link] or cassette lockring tool [paid link]
- Torque wrench [paid link] (with cassette lockring compatibility)
- Chain whip tool [paid link]
- Bike stand [paid link] (optional but helpful)
- Degreaser and clean rags
- Chain checker tool
- Calibrated ruler or digital caliper [paid link]
Identifying Improper CS-6700 Setup
Before making any adjustments, it’s crucial to recognize the symptoms of an incorrectly installed or misaligned cassette. These may include:
- Inconsistent or delayed shifting, especially under load
- Clicking or popping sounds when pedaling
- Chain skipping during acceleration
- Poor gear indexing despite correct derailleur tuning
- Cassette sprockets appearing loose or out of alignment
Such symptoms often point to one or more setup mistakes specific to the CS-6700 [paid link], which features a unique combination of nickel-plated steel cogs and lightweight aluminum carriers.
Installation Oversights That Cause Performance Issues
Many cassette-related problems stem from subtle installation errors. For the CS-6700, key areas to check include:
Lockring Torque Settings
Improper torque application is a frequent culprit. The lockring on the CS-6700 should be torqued to 40 Nm. Anything less can cause lateral play in the cassette, leading to unstable gear transitions and noise. Overtightening, on the other hand, may damage the freehub threads or compress spacers unevenly.
Spacer Misplacement
The CS-6700 requires specific spacers depending on the hub width and cassette version (10-speed vs. 11-speed hub compatibility). Omitting the 1.85 mm spacer when fitting the CS-6700 to an 11-speed hub results in excessive side-to-side movement. This misalignment throws off indexing and chain engagement, especially in the smallest cogs.
Sprocket Orientation
Shimano’s sprockets are designed to fit only one way. However, when installing the CS-6700, it’s possible to accidentally position a sprocket in reverse, particularly with the close-ratio cogs like 12T or 13T. Always align the narrow spline correctly for each cog.
Derailleur Misalignment and Its Impact
Even if the cassette is installed correctly, a misaligned derailleur hanger or poorly adjusted rear derailleur can exaggerate shifting inconsistencies. The CS-6700’s close-ratio design makes it sensitive to even small indexing errors.
Verify that:
- The derailleur hanger is perfectly straight using a derailleur alignment gauge.
- The B-tension screw is adjusted to provide 5–6 mm clearance between the top pulley and the largest sprocket.
- Indexing is calibrated precisely using barrel adjusters.
This ensures optimal lateral movement of the derailleur across the cogset and prevents overshifting or undershifting.
Chain Wear and Compatibility Problems
A worn chain can mimic the symptoms of a bad cassette setup. The CS-6700 cassette is best paired with Shimano 10-speed chains for ideal meshing. Using a non-compatible or stretched chain causes poor engagement, especially in the mid-range gears, which receive the most load.
Check your chain with a wear indicator. If it shows over 0.75% wear, replace it immediately. Chains and cassettes wear together; installing a new CS-6700 cassette with a worn chain will rapidly degrade the new cassette.
Freehub Body and Cassette Interface
The Shimano CS-6700 cassette relies on a tight fit with the freehub body. Dirt, corrosion, or burrs on the freehub splines can prevent the sprockets from seating correctly. This leads to lateral cassette wobble and noisy performance.
Remove the cassette, inspect the freehub for damage, and clean it thoroughly. Apply a thin layer of grease to the splines before reinstallation to improve fit and future serviceability.
Fixing the Setup: Step-by-Step Process
- Remove the rear wheel and place the bike in a stand.
- Inspect and clean the cassette and freehub body.
- Check for correct spacer use, particularly if mounting to an 11-speed hub.
- Install each sprocket carefully, aligning splines and verifying orientation.
- Torque the lockring to 40 Nm using a calibrated torque wrench [paid link].
- Inspect the derailleur hanger for misalignment and adjust if necessary.
- Check chain condition and replace if worn.
- Test gear shifting and fine-tune indexing with barrel adjusters.
Prevention Through Regular Inspection
Once corrected, ensure your CS-6700 setup remains trouble-free by inspecting the drivetrain every 500–1000 km. This includes checking lockring torque, chain wear, and cleaning sprockets to prevent debris buildup.
A properly installed CS-6700 cassette delivers smooth, efficient shifting. Many performance issues arise not from the cassette itself but from oversight during setup. With careful attention to detail and the right tools, these problems are easily preventable.
FAQs
Q1: Do I need a spacer for CS-6700 on an 11-speed hub?
Yes, a 1.85 mm spacer is required when fitting the CS-6700 on an 11-speed hub body.
Q2: Why does my chain skip in the smallest cog?
This could result from a loose lockring, misaligned derailleur, or missing spacer during cassette installation.
Q3: Can I use a 10-speed chain from another brand with the CS-6700?
While other 10-speed chains may work, Shimano chains offer the best compatibility and performance with the CS-6700.
Q4: How tight should the CS-6700 cassette lockring be?
It should be torqued to 40 Nm using a torque wrench [paid link].
Q5: What is the most common installation error with CS-6700?
Incorrect or missing spacers are the most common cause of setup issues, especially when used with 11-speed hub bodies.
Q6: How often should I clean the CS-6700 cassette?
Clean the cassette every 300–500 km or after riding in wet or muddy conditions.