how often should you change the brakes on your bike?

Answer 1

Changes the brakes pads when they are worn or defective.
Adjust them as necessary. Check the links for more.

Simply put, your brakes need to feel like they work, Captis said. When you squeeze the brake levers, they should engage freely. They shouldn't be too loose, and you shouldn't have to work too hard to get them to engage. "There should be a nice smooth feel to them," Captis said. An adjustment may require professional service from a bike mechanic, but you can easily change the brake pads for $5 a wheel. Replace the pads if you can't remember if you've ever replaced them, he said.

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THE BRAKES

Nothing is more dangerous for a biker than having unreliable brakes. Just like monitoring your tire pressure, it’s easy to check your brakes to make sure they’ll be there when you need them.

1. Start by simply rolling the bike while walking alongside it. When you apply the brakes, the bike should stop immediately with no delay or drag.

Step 2. Check the brake tension. Look for the brake-adjusting barrel located on the inside half of the handlebar braking device. Adjusting the barrel counterclockwise will tighten the brake cable, moving the brake pads closer to the rim. Turning the barrel clockwise will loosen the cable and create more space between the pad and the rim. Leave three to four millimeters, but this is mostly a personal preference that you can adjust to your best fit.

Step 3. You can also move the brakes to the left or the right to make sure the pads on one side don’t wear down faster than the pads on the other. There is a brake centering screw on top of each braking clamp on each wheel. Loosen the screw and move the brakes left or right as needed

http://www.boyslife.org/outdoors/outdoor-feature-articles/845/how-to-maintain-your-bike/

2) Most brake pads have a wear line to indicate when they should be replaced but you should also check that they are wearing evenly all over. If some of the pad is missing the rim completely, then the pad will need to be cut down with a Stanley knife or even replaced altogether. Make sure there are no deep grooves in either the pads or the wheel rims. These are signs of wear that may require the replacement of both brake pad and wheel rim.

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