Adjusting A Derailleur On A Bicycle
Introduction
Derailleurs on a bicycle are an essential component that allows the rider to switch gears and adjust the tension of the chain. However, they can become misaligned, making it difficult to change gears or causing the chain to fall off. This can be frustrating, especially when you're out for a ride. Fortunately, adjusting a derailleur is a straightforward process that anyone can do with the right tools and a little patience.
Tools Required
Before you begin, you'll need a few tools to help you adjust the derailleur. These include a set of Allen keys, a screwdriver, and a pair of pliers. You may also want to have a rag handy to clean any dirt or debris off the derailleur.
Step-by-Step Guide
Follow these steps to adjust the derailleur on your bicycle:
Step 1: Shift to the smallest chainring and the largest cassette cog
Shift the bike into the smallest chainring at the front, and the largest cassette cog at the back. This will give you the most slack in the chain, allowing you to adjust the derailleur more easily.
Step 2: Check the alignment of the derailleur
Look at the derailleur from behind the bike and check that it is aligned correctly. The jockey wheel should be directly under the cassette cog. If it's not, adjust it until it is using the barrel adjuster.
Step 3: Adjust the limit screws
The limit screws control the movement of the derailleur. They prevent the chain from shifting off the cassette or chainring. Use the screwdriver to adjust the limit screws until they are set correctly. The high limit screw controls the movement of the derailleur towards the smallest cog, and the low limit screw controls the movement towards the largest cog.
Step 4: Adjust the cable tension
Use the barrel adjuster to adjust the tension of the cable. Turn it clockwise to increase tension or counterclockwise to decrease tension. Check that the chain moves smoothly between gears.
Step 5: Fine-tune the adjustment
Take the bike for a test ride and check that the gears shift smoothly. If they don't, make small adjustments to the limit screws and cable tension until the gears shift smoothly.
Conclusion
Adjusting a derailleur on a bicycle may seem daunting at first, but with a little practice, it becomes easy. Remember to take your time, be patient, and make small adjustments. If you're unsure about anything, consult a professional bike mechanic.