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Cable Cleaning

Dirty or worn cables can create problems when braking and shifting. If you ride in the mud, you'll need to clean out your cables every couple of months. Want to keep the dirt out of the cables? See our mud-proofing page!


A dirty brake cable makes it harder to apply the brakes, and can keep the brakes from rebounding fully away from the rim.

A dirty shifter cable -- especially the rear shifter -- can keep the rear derailleur from shifting smoothly from a larger to a smaller cog.

Cable hang-up can be subtle. But it's the most common cause of intermittent missed shifts when dropping the rear derailleur into a higher gear (smaller cog). Any rubbing, noise, or sense of resistance means the cable needs service.

Check the cable housing (the sections of big black tube that surround the cable).  If you see a sharp bend, the housing needs to be replaced. Look at the exposed sections of cable. If you see fraying, breaks in the individual wires, or loosened wires, the cable itself must be replaced.

Dial the cable-tension adjuster down at the handlebar (clockwise when viewed from the cable), then turn it back one turn. This puts the cable in its starting position.
Undo the cable at the far end (at the brake mechanism or at the derailleur) by loosening the bolt on the retaining clip.
Remove the cable cap. Using needle-nose pliers, grasp the shaft of the cap on the sides opposite of the crimp-marks. Squeeze until the shaft of the cap "rounds up" and rotates freely on the cable.
If there's a rubber boot, slide it off. Check it for holes and tears. A boot that lets mud in (then holds it there) is worse than no boot at all. If the boot is damaged, get a replacement.

This derailleur cable boot has a tear in the nipple where the cable enters.

Slide the cable housing caps away from the housing. Now slide caps and housing off the cable.

 

Keep the pieces organized, so you don't lose any, and don't get them mixed up.

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Degrease cable

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Lube cable
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Clean the cable by rubbing it with a paper towel soaked in degreasing solution. Once the degreaser is completely dry, rub a dry lubricant such as chain-wax into the cable. When the chain-wax is dry, rub the cable smooth with a dry towel.

Clean out the cable housing(s). Squirting WD-40 or pressurized Teflon lubricant through the housing is a quick method. If you have an airgun, follow the WD-40 with a long blast of air. Let the cable housing sections dry.
Wash the boots with soap and water. Use a cotton swab to clean inside the boots.

If you have a barrel adjuster at the end of the cable -- for example, on the rear derailleur, take it off and clean it out.

Apply bearing grease onto the threads of the barrel adjuster. 

Screw it all the way in. (On some derailleurs, where there's a second small hole beyond the barrel adjuster, you may want to slide the adjuster onto the cable before screwing it into the derailleur. Otherwise, the cable may not thread smoothly through both the hole in the adjuster and the hole in the derailleur.)

Now begin reassembling the cable. For each section of housed cable, thread the end cap onto the cable, then the housing, then the next end cap. Fit that section of housing back onto the frame the way it was originally. After that section is fitted, go on to the next section of housed cable, until the cable is completely reassembled.

CAREFULLY slide the cable through the barrel adjuster and towards the retaining clamp. If it stops moving, don't try to force it, or you'll delaminate one of the strands of metal in the cable!

Pull the cable tight and secure the retaining clamp.

Now adjust the cable tightness with the barrel adjuster: for derailleur cables see the section on tuning the front or rear derailleur. For brakes, see the brake tuneup section.

If everything is working, replace the cable cap (or better yet, put on a new one) and crimp it down tight.

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