Road brake cables and housing

How to choose road bike brake cables and housing

Spongy braking is not always down to the pads. More often, the housing has compressed or the cable has developed play inside it. This is the cheapest repair on the bike, and the one that makes the biggest difference to lever feel.

Brake cables and derailleur cables are different

A brake cable measures 1.6 mm in diameter, compared with 1.1 to 1.2 mm for a derailleur cable, and its head has a different shape — cylindrical for road bikes, rather than the pear shape used on mountain bikes. Brake cable housing has a spiral-wound construction, it withstands compression; derailleur housing has longitudinal wires. The two are not interchangeable.

The finishes

• Galvanised steel : the most affordable option, but it needs replacing more often.
• Stainless steel (SUS in Shimano’s range) : corrosion-resistant and the usual choice.
• PTFE- or polymer-coated — Shimano Dura-Ace, Jagwire Slick, SRAM SlickWire: the coating reduces friction. You will notice the difference most on a frame with sharply curved internal routing.
• A polymer-coated cable needs compatible housing: overly abrasive housing damages the coating.

Individually or as a kit

• The cable only is enough when the housing is sound and clean.
• A complete kit — two cables, housing, ferrules and seals — is essential when rebuilding a bike or changing handlebars.
• The kits Jagwire Road Pro and Shimano PTFE come in several colours, so you can match them to your frame.
• The kits Road Elite Sealed add seals at the housing openings, useful for winter riding.

Length and routing

Road brake cables are 2,050 mm long, enough for the front and rear brakes on most frames; 3,500 mm versions are available for long frames and tandems. Trim the housing a little at a time and file the cut end flat: an angled cut crushes the ferrule and creates a stiff spot at the lever.

To find out more: How to adjust your road bike brakes

See also: Road bike derailleur cables and housing · Road bike rim brake callipers · Road bike brake pads