The Shimano CN-HG93 [paid link] is a staple among 9-speed road cyclists seeking reliable, durable chain performance. However, even a high-quality chain like the CN-HG93 [paid link] can occasionally feel rough or unrefined during rides. Poor chain feel can impact not only ride quality but also drivetrain longevity. Understanding why the CN-HG93 [paid link] might not run smoothly and how to correct it is crucial for any cyclist looking to maximize performance.
Common Causes of Rough Chain Feel on the CN-HG93
Several factors can contribute to a rough chain feel, even when the chain is new or recently maintained. Identifying the root cause is the first step toward resolution.
Improper Chain Installation
An incorrect installation is one of the primary culprits behind rough chain performance. If the chain is installed with improper tension or misaligned, it can result in uneven engagement with the cassette and chainrings. For the CN-HG93, ensuring the chain follows the correct directional orientation and that the quick link is securely fastened is essential. Misaligned quick links often create a noticeable rough spot that becomes apparent under load.
Chain Length Errors
The CN-HG93 requires precise chain length for optimal function. Chains that are too short can cause excessive drivetrain tension, while overly long chains may slacken and skip under pressure. The correct method involves wrapping the chain around the largest chainring and largest rear cog (without passing through the derailleur) and adding two full links. This method ensures the derailleur can handle the chain across all gears without strain.
Incorrect Chain Lubrication
Lubrication plays a critical role in the chain’s overall smoothness. Under-lubricated chains increase friction, leading to a gritty, rough sensation during pedaling. Conversely, over-lubrication can attract dirt and debris, creating a similar rough effect. The CN-HG93 responds best to a light, even application of a high-quality chain lubricant followed by thorough wiping to remove excess. Regular cleaning and relubrication intervals will prevent the build-up of grime.
Worn Drivetrain Components
Even if the CN-HG93 is brand new, pairing it with worn chainrings or cassette cogs can cause compatibility issues that result in a rough feel. The Shimano CN-HG93 chain is specifically designed to mesh precisely with Shimano 9-speed components. Excessive wear on these parts can create improper engagement angles and increase vibration. It’s advisable to check the condition of the entire drivetrain before blaming the chain.
Misaligned Derailleur
Rear derailleur alignment is another critical factor. A bent derailleur hanger or improperly adjusted derailleur limits can prevent the chain from settling into the center of each cog. This misalignment forces the CN-HG93 to run at suboptimal angles, generating noise and resistance.
How to Smooth Out the CN-HG93 Chain Performance
Once the cause is determined, targeted solutions can restore the chain’s smoothness and efficiency.
Recheck and Correct Installation
Begin by inspecting the chain installation. Confirm that the quick link is securely closed and seated properly. If in doubt, replace the quick link and reassemble carefully following Shimano’s guidelines. Always ensure that the chain is threaded correctly through both the jockey wheels and that it aligns properly when in the smallest and largest cogs.
Adjust Chain Length Precisely
If improper chain length is suspected, remove the chain and resize it following the wrap-around method. It’s critical to avoid guessing; an incorrect number of links can severely compromise drivetrain performance. After sizing, ensure the chain moves smoothly across the cassette and chainrings without binding or slack.
Optimize Lubrication and Cleaning
Start with a thorough chain cleaning using a degreaser specifically formulated for bike drivetrains. After drying the CN-HG93, apply lubricant drop by drop to each link pivot, rotating the crank backward to distribute evenly. Wipe away all excess lube with a lint-free rag to prevent dirt accumulation. This process should become a regular part of your maintenance routine, ideally every 150-200 miles or after wet rides.
Inspect and Replace Worn Components
If roughness persists despite a well-maintained chain, carefully inspect the cassette and chainrings for signs of wear. Shark-fin-shaped teeth or teeth that appear more pointed than new components indicate excessive wear. Replacing these parts may be necessary to match the new CN-HG93 and achieve smooth performance.
Realign the Derailleur
Using a derailleur hanger alignment tool, check the alignment of the rear derailleur hanger. Even slight deviations can cause shifting issues and poor chain engagement. After confirming the hanger is straight, fine-tune the derailleur’s limit screws and cable tension to ensure precise shifting.
Signs of a Properly Functioning CN-HG93 Chain
A properly installed and maintained CN-HG93 chain will deliver:
- Smooth, quiet operation across all gears
- Quick and precise gear changes
- Minimal resistance during pedaling
- Long service life without premature wear
If your CN-HG93 does not meet these benchmarks, revisiting the steps outlined above should resolve most issues.
When to Seek Professional Help
While many cyclists can address rough chain feel with basic tools and mechanical knowledge, persistent issues may warrant professional inspection. Skilled mechanics can diagnose complex problems such as subtle frame misalignments, advanced drivetrain wear, or factory defects in components.
Maintaining a smooth-running CN-HG93 chain ensures an enjoyable, efficient ride and protects the overall integrity of your bike’s drivetrain. By paying close attention to installation details, lubrication routines, and drivetrain compatibility, cyclists can unlock the full potential of their Shimano 9-speed systems.