Are the bicycle brakes blocked and preventing you from using the bike? When the brake pads rub against the wheel or stick to it completely, you can also repair them yourself; checking the pads, lubricating the fulcrums of the levers and modifying the cables are all operations that you can do independently. If the damage is more serious, you need to take the bike to a workshop or replace the entire brake system.
Steps
Part 1 of 3: Basic Repairs
Step 1. Check that the pads are not worn
When very damaged, they stick to the wheel rim despite all your adjustments; if they are less than 6mm thick, it is time to replace them. They should be facing slightly inward, meaning the front edge of the pads should touch the wheel rim when you apply some pressure on the brake lever.
Step 2. Check the edge of the skates
Some have a kind of "tongue" that sticks out on one side near the hub. If the material surrounding it is worn, the tongue may stick to the wheel rim.
File the tab. If you find that it protrudes too much, you can wipe off some with a razor blade to allow the wheel to spin freely. Be careful not to remove too much thickness, otherwise the brakes won't work
Step 3. Lubricate the fulcrums of the levers
These are the points on which the individual brake elements pivot. If the levers feel stiff to you, try oiling the cylindrical pin. Apply a little oil on each fulcrum; you can use a light engine oil or bike specific lubricant for best results. After this repair, you should feel the levers feel responsive as you pull them.
Do not apply lubricant to the pads, wheel rims or brake discs, as this could damage the pads and create big problems when braking
Part 2 of 3: Adjust the Cables
Step 1. Inspect the cables
If the levers show no problem and the pads are not adhering to the wheel, the cables may be responsible for the malfunction. You should be able to repair them by hand without the help of a mechanic; if, however, you encounter difficulties, do not hesitate to take the bike to the workshop.
Step 2. Adjust the length of the cables to increase the tension
This procedure is perhaps the simplest repair you can do on the brake system. On a normal bicycle, you can make fine adjustments without the need for any special tools. Just turn the barrel on the end of the cable sheath to find the best tension. On classic "V" brakes, the cylinder is located on the lever at the point where the cable comes out.
Step 3. Lubricate the cables
Purchase a spray product with a small straw. Spray the oil inside the cable sheath at the ferrule: the plug through which the cable enters the sheath under the brake levers. Use a can of light engine oil with a small nozzle, or purchase a bicycle brake cable lubricant from a specialty store. Proceed with small sprays so as not to over-impregnate the cables.
WD-40 and other industrial degreasers can "wash" factory grease from cables; when the WD-40 evaporates, it leaves only a small amount of lubricant
Step 4. Remove the sheath
If the cable is still stiff, try to remove the gasket. First, remove the clamp at the caliper or lever; afterwards, pull the cable from the opposite end. If you have extracted it, use a solvent spray (or even WD-40) to remove all traces of dirt and residue from the sheath. Apply a light coat of lithium grease or motor oil to the cable and reinstall it if it is not damaged.
- Slip the cables into their respective sheaths. Feed the free end through the clamp you removed the cable from.
- Check the "free play", which is how far you can squeeze the lever before the brakes kick in. Tighten the clamp when the pads are approximately 6mm from the wheel rim with the levers released.
Part 3 of 3: Advanced Repairs
Step 1. Drain and replace brake fluid
This repair is only possible on plumbing systems. If your bike is equipped with one of these systems, you will need to change the fluid from time to time.
- Check that there are not many bubbles in the replacement fluid, otherwise the brakes can become "spongy".
- Never use mineral oil as a brake fluid if the instruction manual states that you should only use DOT (US Department of Transportation approved) oil. Likewise, do not use a DOT liquid if the instruction manual indicates that the system works with mineral oil. If the last time you made the switch, you mixed the two substances, this could be the source of your problems.
Step 2. Consult the user and maintenance manual for specific instructions
There are many models of plumbing systems and each is slightly different, so read the manual for detailed information. If you don't have the brochure, try to figure out what exact plumbing model you have and search online for instructions. If you're still having trouble, consider going to a bike shop.
Step 3. Adjust the pliers
These are the part of the brake system that allows the pads to stick to the wheel. Here's how to fix them:
- Unscrew the pads located inside the calipers, above the wheels. These are small pieces of rubber on the underside and inside of the caliper itself, which must make contact with the wheel.
- Adjust the brake so that it is 3-5mm from the tire rim.
- Tighten the skates, rotate the tire keeping it suspended in the air and check the brakes; make further changes if necessary.
Step 4. Take the bike to the mechanic
If all the remedies described so far have not led to any results, it may be easier to take the vehicle to a specialized workshop. Look for a reliable one in the area.
Read the online reviews on the various workshops before going there; this way, you can get an idea if the mechanic can help
Advice
- Read this article for more advice.
- You can do some research online to find specific brake adjustment instructions.
Warnings
- Remember to re-engage the brake immediately after reassembling the wheel!
- Check the brakes before every ride.
