Noisy shifting is one of the most frustrating experiences for any cyclist, particularly when it comes from a component as critical as the chain. The Shimano CN-HG93 [paid link] chain is known for its reliability and smooth performance, but like any drivetrain part, it can develop issues if not properly maintained or installed. In this guide, we’ll walk through diagnosing and fixing noisy shifting specifically related to the CN-HG93 [paid link], ensuring your ride remains as silent and efficient as possible.
Understanding the CN-HG93 Chain
The CN-HG93 [paid link] is a 9-speed chain engineered by Shimano, designed for both road and mountain bike applications. It features precision engineering with Hyperglide technology, ensuring smoother gear transitions. Despite its high-quality build, factors such as wear, dirt, or misalignment can affect performance, resulting in unwanted noise during shifting.
Tools Required
- Chain checker tool
- Chain breaker tool
- Shimano-compatible chain pin or quick link
- Chain lubricant (dry or wet lube [paid link] based on conditions)
- Clean rag
- Mild degreaser
- Torque wrench [paid link]
- Cassette wear checker
- Chainring inspection gauge (optional)
Common Causes of Noisy Shifting with the CN-HG93
Shifting noise can stem from various sources, but when isolated to the chain, typical causes include:
- Chain wear and elongation
- Incorrect chain length
- Inadequate lubrication or contamination
- Improper installation
- Misalignment with cassette or chainrings
- Incompatibility with drivetrain components
Identifying the exact cause is crucial before proceeding with repairs.
Step-by-Step Diagnosis
Inspecting Chain Wear
First, use a chain checker tool to measure chain wear. For the CN-HG93, a wear reading beyond 0.75% indicates it’s time for a replacement. Worn chains no longer mesh correctly with cassette teeth, causing noisy shifts and increased drivetrain wear.
Checking Chain Length
If the chain was recently installed, improper sizing might be the issue. Shimano recommends wrapping the chain around the largest chainring and sprocket without going through the derailleur, then adding two full links (one inner and one outer). An incorrectly sized chain can pull the derailleur out of alignment or fail to maintain proper chain tension, resulting in noisy shifting.
Evaluating Lubrication and Cleanliness
Chains exposed to dirt, water, and road grime lose their lubrication properties, causing friction and noise. Inspect the CN-HG93 for signs of contamination. If dirt buildup is present, a thorough cleaning is required. Degrease the chain with a mild solvent, wipe it dry with a clean rag, and reapply a fresh layer of chain lubricant.
Verifying Installation Quality
Improper chain installation, especially with pin-based joining systems like the Shimano connecting pin, can lead to tight links. Check for stiff or binding links by flexing each one side to side. Tight links create inconsistent movement across cogs, leading to irregular and noisy shifting. Replace any stiff links or rejoin the chain properly with a new Shimano connecting pin or an approved quick link.
Drivetrain Component Compatibility
Although the CN-HG93 is versatile, it must match the rest of the drivetrain. Confirm that the cassette and chainrings are 9-speed compatible and in good condition. Even a perfectly functional chain can produce noise if mated with excessively worn or incompatible components.
Fixing the Noisy Shifting
Replacing a Worn Chain
If diagnosis reveals excessive wear, replace the CN-HG93 chain immediately. Continuing to use a worn chain will not only worsen noise but will also accelerate cassette and chainring wear. Use a Shimano pin or a quick link for joining, ensuring the link is properly seated.
Correcting Chain Length
If the chain length is incorrect, remove the chain using a chain breaker tool and adjust it to the correct size. Follow Shimano’s method for sizing to avoid shifting inefficiencies.
Cleaning and Lubricating the Chain
After cleaning with a degreaser and ensuring the chain is dry, apply a suitable lubricant. For dry conditions, a dry lube [paid link] is preferable to minimize dust attraction. For wet or muddy conditions, a wet lube [paid link] provides better resilience. Lubricate each link individually and wipe off the excess to prevent grime accumulation.
Addressing Tight Links
Tight links can be worked loose manually by flexing the chain side to side. If the problem persists, rejoin the chain using a new connector pin or quick link. Avoid forcing the chain through the drivetrain, as this can cause permanent damage.
Inspecting and Replacing Worn Drivetrain Components
If noise persists despite chain maintenance, check the cassette and chainrings for hooked or shark-toothed teeth. Severely worn components should be replaced. Mismatched wear between chain and cassette can also cause persistent noise.
Preventative Measures for Quiet Shifting
Regular maintenance is key to preventing noise from your CN-HG93 chain. This includes routine cleaning and lubrication, checking for wear every 500–1000 km depending on riding conditions, and ensuring drivetrain components are compatible and in good condition.
Using a consistent maintenance schedule not only prolongs the life of the chain but also maintains the overall efficiency and enjoyment of your rides.
Final Thoughts
Diagnosing and fixing noisy shifting related to the Shimano CN-HG93 chain requires a methodical approach. By inspecting wear, verifying installation quality, maintaining cleanliness, and ensuring compatibility, you can restore your bike’s shifting performance to its optimal state. Regular attention to these details ensures that your CN-HG93 will continue to deliver smooth, reliable performance for thousands of kilometers.