There are various reasons why you may need to replace your bike’s brake cable, but it’s usually because of wear or breakage. Bike brake cables are made of steel braids and are very resistant: there’s a metal terminal at one end, which can be spherical or barrel, which allows the cable to firmly connect to the brake lever. The cable is subjected to considerable stress and, sooner or later, may show signs of wear. The cables typically fray near the clamp that connects them to the brakes, or at the terminal, or they might fray or break along the path in the sheath. Another frequent problem is found in bikes that haven’t been used for months, whose brake cables and sheaths had not been adequately dried and lubricated at the time of storage. In these cases oxidation can occur inside the sheath: the cable slides poorly, the braking becomes “pasty” and the lever is hard to operate. In these situations, the cables must be replaced, and sometimes even their sheaths.