How To Lubricate Brake and Shift Cables

Road bike brake wire and mountain bike brake wire differ in the shape of the small head found at one end of the wire. This head fits into a specially machined space (a “stop”) in the lever and holds the wire in place. Certain manufacturers make wire that has a road head at one end and a mountain head at the other. If you buy that kind of wire and don’t know what to do with it, simply clip off the head you don’t need with a good set of cutters that won’t fray the wire. It’s best to clip it off right below where the head meets the wire to ensure that you still have the full length of the wire to work with.

On levers that combine the brake levers and shifters into one assembly (“integrated” levers), the stop for the brake housing is often recessed into the back of the lever, and can be hard to reach. It helps to first run the wire through the lever as shown, then place a section of brake housing onto the end of the wire and slide it up along the wire until it reaches the stop in the lever, using the wire as a guide to position the housing right up against the stop. Always make sure that the housing fits as snugly as possible in the stop before taping the handlebars. If it’s not, the brake will not perform up to its full potential, and will feel less responsive at the lever.

Some mountain bike brake levers don’t have an opening in the head of the lever body like the lever shown here, through which the stop is visible. On those levers, access the stop by pulling the lever all the way back, as if you were braking. This will expose the stop, which may be drilled directly into the lever, or linked to the lever in the form of a cam. Then insert the head of the wire into the stop, guide the wire into the slots in the lever body, knurled nut (“adjusting barrel”), and lockring, and release the lever again.

When installing shift wire, if the wire won’t pass through the shifter, check to make sure that the shifter is shifted to its lowest position. On a rear shifter, this is the position in which the chain would be on the smallest cog. On a front shifter, this is the position in which the chain would be on the smallest chainring.

After you size your housing and measure out the length you need, add a bit to that length in case you need to trim it after you cut it. If it turns out that you don’t need to trim it, the effect of the additional length will be insignificant. Remember that it’s always better to cut your housing too long than it is to cut it too short. Alternately, many professional shop and team mechanics trim housing using a bench grinder or a rotary tool with a grinding disc, like those made by Dremel or Craftsman. If you have access to such a tool, you’ll always be able to remove any spurs from the cut end of the housing without having to cut it again.

In addition to reaming the inner liner of shift housing after making your cut, it helps to pinch the housing itself back into a circular shape. This will make it easier to fit a ferrule onto the end of the housing before running the wire through it.