Why Does My Bike Skip Gears and How to Fix It

Have you ever found yourself in the middle of a ride, only to experience your bike's gears suddenly skipping? This frustrating issue can leave you feeling stumped. Fortunately, there are several common causes, and appropriate solutions can often be found. In this article, we'll explore the reasons behind gear skipping and guide you on how to address the issue, from DIY troubleshooting to professional help.

Is It the Rear Derailleur?

The most common cause of gear skipping is a poorly tuned rear derailleur. If you notice your gears skipping, it's likely that the rear derailleur is out of tune. To fix this, you'll need to adjust the 2 tension screws on your derailleur using a screwdriver. This process may require some fine-tuning, so if the issue persists, it's advisable to visit a bike mechanic for a professional adjustment.

Chain and Gears Wear

Another frequent culprit is the wear and tear on your chain and gears. If the chain is worn, it may not mesh perfectly with the cogs, leading to skipping. Additionally, the chainrings can wear down, resulting in skipping gears, especially at their most heavily loaded points where maximum torque is delivered. In such cases, you might need to replace the worn chainring. This is particularly common in the middle chainring of a 3-chainring setup, often after extensive use. A new off-brand chainring can be obtained for around $50.

Mechanical Issues

Less commonly, other mechanical issues might cause gear skipping. For instance, if you have a multi-speed motorcycle, the gear dogs—the pegs that fit into the recesses of the adjacent gear on the shaft—can wear out. This wear can cause the gears to slip out of alignment during acceleration, leading to gear skipping. While this isn't a common issue for bicycles, it's worth considering if you have a related issue with your motorcycle.

Troubleshooting Gear Skipping

Here are some steps you can take to diagnose and potentially fix gear skipping on your bike:

Check for Chain Stretch: Over time, chains stretched due to wear and tear. To check for this, place a ruler or tape measure on the chain and measure the distance between two pins. The standard measurement is 1.27 inches. If the measurement is consistently greater than 1.27 inches, the chain is stretched and should be replaced. Examine Chain and Cogs: Look for bent or worn teeth on your chainwheels and cogs. Worn teeth can cause skipping. Sometimes, stiff sections in the chain can cause skipping, especially if the chain doesn't bend properly. Lubricate the chain and move it around to ensure it moves smoothly. Derailleur Jockey Wheels: Ensure that the derailleur jockey wheels are not stiff or malfunctioning. These wheels guide the chain and need to turn smoothly. If they are stiff, you may need to clean or replace them. Align the Gear Settings: Sometimes, the gear settings can be misaligned. Make sure the chain aligns properly with each cog when in use. If the chain skips on certain gear settings, it could be a sign of misalignment. Consider the settings on your bike and ensure they are correctly set up.

Professional Assistance

While some of these issues can be fixed with DIY solutions, others may require professional assistance. If you're unsure about the issue or find it difficult to fix, it's best to take your bike to a local bike shop. Mechanics can provide expert advice and fix any components that need replacement.

Conclusion

There are many potential reasons why your bike's gears might start skipping. Common causes include worn chains, poorly adjusted derailleurs, and worn cogs. By understanding the causes and taking the appropriate steps, you can address the issue and enjoy a smoother ride. If you're unsure or need assistance, don't hesitate to visit a bike mechanic or shop.

For more guidance, you can find numerous instructional videos online. A good starting point is the Parktool website, which offers detailed tutorials on bike maintenance and repair.