The Shimano CS-6700 [paid link] cassette is a high-performance 10-speed component designed for road cyclists who demand smooth and precise shifting. As part of Shimano’s Ultegra 6700 series, it offers excellent durability and weight savings, making it a popular choice among serious riders. However, even a high-quality cassette like the CS-6700 [paid link] can underperform if not installed correctly. Improper installation can lead to poor shifting, excessive wear, and drivetrain noise.
This guide will walk you through the most common installation errors associated with the Shimano CS-6700 [paid link] cassette and provide expert insight into how to avoid them. By understanding these pitfalls, you can ensure a smooth, efficient drivetrain that enhances your riding experience.
Tools Required
- Cassette lockring tool [paid link]
- Torque wrench [paid link]
- Chain whip
- Grease or anti-seize compound
- Clean rag or towel
Skipping Crucial Cleaning Steps
Before installing any cassette, the freehub body must be completely clean. Skipping this step leads to dirt or grit becoming lodged between the cassette and the hub, which can compromise alignment. With the CS-6700, which features an alloy carrier for weight savings, improper seating on a dirty hub can cause uneven torque distribution, eventually leading to wear or warping.
Thoroughly clean the freehub body with a degreaser and a clean rag. Inspect for burrs or damage and ensure all surfaces are smooth before mounting the cassette.
Incorrect Spacer Placement
The CS-6700 is compatible with Shimano 10-speed road freehubs, but specific wheelsets may require an additional 1.85 mm spacer if the hub is designed for 11-speed cassettes. Failing to include the proper spacer results in poor cassette alignment and uneven cog spacing. This causes inconsistent shifting, chain skipping under load, and excessive drivetrain noise.
Double-check the hub specifications and ensure the correct spacers are installed in the right order before tightening the lockring.
Under or Over-Torquing the Lockring
The lockring on the CS-6700 cassette should be torqued to Shimano’s specified 40 Nm. Riders often install cassettes without a torque wrench [paid link] or rely solely on feel, which can lead to under-tightening or over-tightening.
Under-torquing allows the cassette to shift slightly under power, creating a clicking noise or uneven shifting. Over-torquing can damage the lockring threads or deform the carrier body, especially in lightweight alloy hubs.
Always use a calibrated torque wrench [paid link] to achieve the correct specification and avoid unnecessary damage.
Forgetting to Grease the Freehub Splines
Dry installation of the CS-6700 cassette onto the freehub body can lead to micro-movements during pedaling, resulting in creaking or even notching of the alloy freehub splines over time. Greasing the splines minimizes friction and prevents corrosion, ensuring the cassette mounts smoothly and stays in place.
Apply a light coating of grease or anti-seize compound to the freehub splines before sliding on the cassette cogs. Be careful not to over-grease, as excess can attract dirt.
Improper Cog Alignment on the Carrier
The Shimano CS-6700 cassette uses a one-piece carrier for the largest cogs and individual cogs for the rest. Each cog has a specific spline configuration that ensures correct orientation. If a cog is forced on in the wrong orientation, it will not sit flush, causing chain alignment issues and skipping.
Always align the smallest spline of each cog with the matching notch on the freehub. If it doesn’t slide on easily, check alignment—never force the cog into place.
Skipping Final Indexing After Installation
Installing a cassette is only part of the job. After mounting the CS-6700, the rear derailleur indexing must be fine-tuned to account for cog spacing and chainline. Riders often skip this step, leading to laggy or inconsistent shifting.
Adjust the rear derailleur’s barrel adjuster to ensure the jockey wheels align cleanly with each cog. Test shift through all gears and fine-tune until the chain moves smoothly and without hesitation.
Reusing a Stretched Chain
Installing a new CS-6700 cassette with an old, stretched chain is one of the fastest ways to wear out the new component. A worn chain won’t mesh cleanly with the new cog teeth, leading to poor shifting and rapid wear. In extreme cases, it can also damage the carrier cogs.
Whenever you replace a cassette, inspect the chain using a chain wear checker. Replace the chain if it’s beyond 0.75% wear to ensure optimal performance and longevity of both parts.
Not Checking Derailleur Hanger Alignment
An improperly aligned derailleur hanger can mimic the symptoms of poor cassette installation—skipping, missed shifts, or hesitation. After installing the CS-6700, verify that the derailleur hanger is straight using a derailleur hanger alignment tool.
Misalignment of even a few millimeters can make accurate indexing impossible, especially with the tighter tolerances of a 10-speed system.
Conclusion
Precision is critical when installing the Shimano CS-6700 cassette. From proper spacer usage to torque settings, every detail plays a role in how the cassette performs. Avoiding the common mistakes outlined above ensures that your drivetrain operates smoothly, shifts cleanly, and lasts longer.
Taking a few extra minutes during installation to follow best practices will save you from hours of troubleshooting later. Whether you’re a weekend warrior or a competitive rider, mastering the nuances of cassette installation makes all the difference in drivetrain performance.