Cables and housings

Stainless steel is the standard for road bikes; polymer cables are smoother but more expensive; galvanised cables should be avoided on road bikes. Stainless steel cables (Shimano SP41, Jagwire Pro) are corrosion-resistant, long-lasting and provide precise shifting. Polymer-coated cables (Shimano Optislick, Gore Ride-On) are impregnated with a permanent PTFE lubricant that reduces friction in the housing by 20–30%: smoother gear changes and more progressive braking, particularly appreciated in the rain. Higher price and increased susceptibility to abrasion. Galvanised cables rust quickly and are reserved for entry-level models.

Four tell-tale signs: slow return of the lever to the rest position, misaligned indexing, creaking under load, or visible corrosion at the ends. A crushed or damaged brake cable housing creates a point of resistance that slows the cable’s return: the lever returns sluggishly and braking lacks bite. On a derailleur cable housing, increased friction results in imprecise gear changes or a derailleur that fails to position correctly after shifting. Check by removing the cable: a bare cable that does not slide easily through the housing indicates that the housing needs replacing.

Generally speaking, yes, but some compatibility checks are necessary depending on the system. Cable diameter standards (1.1 mm for gears, 1.5 and 1.6 mm for brakes) are universal. Shimano SP41 and Jagwire Road Elite cables are interchangeable on the vast majority of bikes. Gore Ride-On uses a specific system with dedicated end caps that do not work with other cables or other cables. For Di2 or AXS electronic groupsets, there are no mechanical cables, but specific, non-interchangeable electrical wires.

Spray PTFE lubricant into the cable housing entry points every 2,000 to 3,000 km. The effective method: slightly loosen the cable, insert the nozzle of a light lubricant (WD-40 Specialist PTFE, Shimano Premium Lube) into the housing from the end, and spray whilst gently pulling the cable. This distributes the lubricant along the entire length. Do not lubricate Gore or Shimano Optislick polymer cables: the built-in PTFE coating is degraded by external lubricants. Waterproof cables (Gore, Jagwire Pro) must be checked at the ends to ensure that the end caps are intact.

A precision cable cutter, a tool for crimping the ends of the housing, an awl and lubricant: this is the minimum equipment required. A high-quality cable cutter (Park Tool CN-10) is essential for achieving a clean cut without crushing the housing. A poor-quality cable cutter leaves burrs that can snag the cable. The awl or a pointed tool is used to reopen the inner passage of the gear housings (liner) after cutting. The crimping tool (for hose ends) prevents the hose from fraying. Allow 1 to 2 hours for a complete cable and hose replacement on a road bike. Then carefully adjust the derailleur indexing.

Gear cables are generally 2,000 mm long, brake cables 1,700 to 2,000 mm; cutting to the correct length is crucial. If too short, the cable creates tension on the housings where the handlebars bend. If too long, it forms loops that increase friction. The rule: the cable must allow the handlebars to be turned fully in both directions without any visible tension on the housings. For drop bars, the calculation is made by simulating the handlebars turned fully to one side. Cable and housing kits (Shimano, Jagwire, Gore) provide generous lengths to be cut to size.

Yes, frames with fully internal cable routing require cables with a twist-resistant liner. On fully integrated frames (Trek Madone, Specialized Tarmac SL8), the cables run inside the handlebars, head tube and frame for several tens of centimetres. Standard cables can twist or get jammed in these narrow channels. Jagwire Road Pro or Shimano SP41 reinforced cables are recommended for these set-ups. Some frames require cables of a specific diameter (4.5 mm or 5 mm), as specified in the manufacturer’s documentation.

Water, salt and mud get into the cables and cause corrosion, which increases cable friction. In winter, riding in the rain and cold weather causes water to seep into the cables through the ends and micro-cracks. The water causes corrosion within a few hours on non-stainless steel cables, and creates abrasive mud that gradually erodes the inside of the housing. The first thing to do when winter is over: remove the cables, inspect the housings and replace them if necessary. On bikes used all year round, opt for waterproof cables (Gore, Jagwire) with sealed end caps.

Inject PTFE spray through the ends of the housing whilst pulling the cable slightly to one side.Loosen the cable screw on the derailleur side (or the caliper side for brakes), pull the cable out of the housing by 3 to 5 cm, insert the nozzle of the PTFE spray into the housing opening and spray, allowing the cable to slide back and forth several times within the housing. This method partially restores lubrication without requiring a complete replacement. It is effective on cables that are still in good condition but slightly dry. If the cable is cracked, crushed or very old, a complete replacement remains the best long-term solution.