Cables

Bike cables consist of an inner steel wire and an outer cable housing. The inner wire is free to slide back and forth inside the housing, while the housing serves to keep the inner wire in place. The cable assembly needs to be clean and free of sharp kinks in order to function properly. I'll show you how to clean and lubricate your cables for best braking and shifting performance. I will use a brake cable on a Schwinn Varsity for reference.

On some bikes you don't have to unbolt the cable from your brakes or derailleurs in order to clean it. If the cable stops on the frame have a cutout in them you can slacken the cable, pull the housing out of the cable stop, and slide the inner wire through the cutout:

Now you can just slide the housings over and then clean and oil the part of the inner wire that rests inside the housings. If your bike doesn't have split housing stops the you have to unbolt the cable first:

If you're replacing the cable then you'll have to do this part anyway. Once the cable is free, just slide the inner wire out of each housing piece, then unhook it from the brake or shift lever:

Now you can clean the cable or just replace it if it's frayed or really rusty. Make sure to oil the inner wire a lot before you reinstall it. On these old road bike levers you need to hook the cable end into a rotating barrel inside the lever for installation:

 Here's another shot showing how the cable attaches to an old style brake lever:

 

Once it's attached to the lever, just thread the cable through the housing pieces and reattach it to the brake (or derailleur if you're doing a shift cable). I like to hold the brake pads to the rim, then pull the slack out of the cable and bolt the brake cable down:

Test if the bolt is tight enough by pulling on the brake lever as hard as you can. If the cable slips then tighten it up some more (be careful though, these little bolts break really easily). You can use the barrel adjuster to fine tune the brake feel once it's bolted down.