The SRAM PC-1170 [paid link] chain is designed to deliver smooth, precise shifting for both road and gravel cycling. However, cyclists may sometimes experience an issue known as “skipping,” where the chain fails to engage properly with the cog teeth, leading to inconsistent pedaling performance. This problem can be frustrating, but with the right approach, you can easily diagnose and correct it. Below, we’ll cover the reasons why your SRAM PC-1170 [paid link] chain might feel skippy and provide actionable steps to resolve it.
Understanding Chain Skipping
Before addressing the causes of chain skipping, it’s important to understand what it feels like. Skipping typically manifests as a sudden, jerky movement in the drivetrain when pedaling, often accompanied by a lack of smooth engagement between the chain and cog. This can occur during shifting or even when the bike is in a fixed gear, especially under load. Skipping usually happens when the chain is unable to catch the teeth on the cogs properly, leading to a temporary “slip.”
Common Causes of Skipping with the SRAM PC-1170 Chain
Several factors could lead to a skipping chain, some of which are easy to fix, while others require more attention to detail. Below are the most common causes:
1. Worn Chain or Cogs
One of the most common reasons for a skippy chain is wear on the chain or the cogs. The SRAM PC-1170 chain, like all chains, wears out over time, particularly after thousands of miles of use. A worn chain no longer fits tightly between the cog teeth, causing it to skip under load.
How to Check: Use a chain checker tool to measure the wear on your PC-1170 chain. If the chain is stretched beyond the recommended limit (typically 0.5% to 0.75% for road chains), it may cause skipping. Additionally, inspect the teeth of the cogs for any signs of wear, such as rounded or chipped edges.
2. Dirty or Dry Chain
Dirt, grime, and a lack of lubrication can cause your chain to skip. When the chain is not adequately lubricated or is contaminated with dirt, it doesn’t engage the cog teeth smoothly. This friction can cause skipping, especially in higher gears.
How to Fix: Clean your SRAM PC-1170 chain thoroughly using a degreaser and a soft brush. After cleaning, apply a suitable lubricant and wipe off any excess. Regularly cleaning and lubricating your chain can significantly reduce skipping and prolong the lifespan of both your chain and cogs.
3. Incorrect Chain Length
A chain that is too short or too long can cause skipping. If the chain is too short, it will be under tension during shifting, which can lead to skipping when the derailleur is under load. Conversely, an overly long chain can create slack, causing the chain to slip when shifting.
How to Adjust Chain Length: To ensure the proper chain length for your SRAM PC-1170, shift into the largest cog and chainring, and then check if the chain is too tight or too loose. If necessary, remove links to shorten the chain or add links if it’s too long. Ensure that the chain is properly sized for smooth shifting and performance.
4. Misaligned Derailleur or Poor Adjustment
A misaligned derailleur hanger or improper derailleur adjustment can cause the chain to skip, particularly when shifting under load. If the derailleur is not properly aligned, the chain may struggle to move smoothly between the cogs, resulting in skipped shifts.
How to Adjust: Start by checking that your derailleur hanger is straight using a derailleur alignment tool. If the hanger is bent, straighten it or replace it. Next, ensure the derailleur is properly indexed by adjusting the limit screws and fine-tuning the barrel adjuster for smooth shifting.
5. Faulty or Incorrectly Installed Cassette
If your cassette is not installed correctly or is defective, it can cause poor engagement between the chain and the cog teeth, leading to skipping. In particular, a misaligned or loose cassette can create uneven pressure on the chain during shifting.
How to Fix: Check that the cassette is securely installed and that the lockring is torqued to the manufacturer’s recommended specifications. If the cassette has been used for many miles, inspect the teeth for wear and consider replacing it if necessary.
How to Instantly Improve Your SRAM PC-1170 Chain Performance
Now that you’ve identified the possible causes of skipping, here are some actionable steps you can take to improve your SRAM PC-1170 chain’s performance and eliminate skipping:
1. Replace a Worn Chain
If your chain has exceeded its wear limit, replacing it is the most effective solution. A new SRAM PC-1170 chain will engage the cogs more efficiently, eliminating the skipping issue. When replacing the chain, it’s also a good idea to inspect the cassette and chainrings for wear, as these components will also impact performance.
2. Perform a Chain Clean and Lube
A dirty, dry chain is one of the leading causes of skipping. By thoroughly cleaning the chain and re-lubing it, you can restore smooth performance. Make this a regular part of your bike maintenance routine to keep your drivetrain running smoothly.
3. Adjust the Derailleur
Ensure your derailleur is properly aligned and adjusted. Take time to fine-tune the indexing so that the derailleur moves smoothly between the cogs. This will help eliminate skipping, especially during gear changes.
4. Check and Replace the Cassette if Needed
If the cassette is worn out or improperly installed, it will not mesh well with the chain, leading to skipping. Check the condition of the cassette and replace it if necessary. Always install the cassette carefully and torque the lockring to the correct specification to prevent any issues.
5. Proper Chain Length
A correctly sized chain is crucial for smooth drivetrain operation. Make sure your SRAM PC-1170 chain is properly sized to avoid chain slack or excessive tension. Adjust the chain length as necessary and double-check that it runs smoothly in all gears.
Final Thoughts
Chain skipping can be a frustrating issue, but it’s usually easily resolved with the right adjustments. By maintaining your SRAM PC-1170 chain with regular cleaning, lubrication, and proper adjustment of your drivetrain components, you can ensure a smooth, reliable performance on every ride. If you continue to experience skipping despite taking these steps, it’s a good idea to consult a professional bike mechanic for a thorough inspection.