Check Your Cables:
Brake cables should be regularly inspected and replaced if worn, frayed or in any way damaged. The most common areas for damage to occur are at the clamp bolt on the brakes (a damaged cable is shown below-left) and at the barrel end of the cable inside the brake levers (below-right).
You should also inspect the outer cable for signs of damage, cuts or sharp kinks. In most cases the outer cable is very durable and may be reused many times.
Fit New Cables:
1. To remove the old cables slacken the clamp bolt on the brakes. If there is a crimp fitted to the cable end cut this off. Pull the cable through and remove from brake lever.
2. Before you fit a new cable take the opportunity to clean your cable outers. Using a spray lubricant (e.g. GT85, WD40 or similar) down the cable outer to remove any dirt. (You might be surprised how much black gunge comes out, so be careful where you do this!)
3. Starting at the brake lever feed your new brake cable down through the outer casing until the end reaches the brakes themselves. Use the same routing as before and if there are exposed sections of cable (i.e. that run along the top or down tubes of your bike) fit cable 'donuts' to stop the wire slapping against your frame and damaging the paintwork.
4. Make sure the barrel end of the cable is fitted in the brake lever (see picture no. 2, top of page) and checking the cable routing one last time. Pull the cable tight at the brake end and clamp the cable lightly under the clamp bolt. You may need to spend a little time adjusting the brakes so that the wheel spins freely, yet is stopped with a pull on the brake lever. Most brake levers have a cable adjuster for fine tuning, but you should attempt to get approximately the right length of cable before using these. Once satisfied that the brake pull is right, tighten the brake clamp bolt so the cable is secure.
5. To finish the job cut any excess cable leaving about 6cm spare. Use good quality cable cutters to avoid fraying your new cable. The cutters on the sides of pliers aren't normally sharp enough for this task, although household wirecutters normally work if you heat the cable before cutting (try a gas flame - culinary blow torch or a cigarette lighter). You should aim for a clean finish (see below right). Try a few practice cuts on a spare bit of cable (e.g. the old one you removed).
Once cut fit a metal end cap to crimp the end of the cable, prevent fraying and to stop yourself from getting scratched on the sharp metal.
6. Before riding check once again that your wheels spin freely and that when you pull the brake lever both brake pads make contact with the wheel rims.
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Yeke Bike Parts
Safety: If in any doubt about the safety of your bike (and in particular brakes) you should seek expert advise from a local bike shop. Never use damaged cables or substitute thinner gear cables (inners or outers).