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Your braking is less powerful. Your gear changes require significant effort on the levers and lack precision. The culprits are often these four steel cables which connect derailleurs and brakes to their respective levers, as well as the sheaths which protect these cables.
Exposed to the elements and subjected to significant mechanical stress, the cables must be given special attention. They are made from a braid of steel filaments, stainless or not, at the end of which a lead head is molded anchoring them to the lever.
Renovating cables and sheaths on a bike does not pose any difficulty, apart from cutting the sheaths correctly (without flattening them), which requires cable and sheath cutter pliers.
Remember to inspect the cables for possible defects.races corrosion and any fraying or partial breakage. Particularly check the sections where the cables enter and exit the conduits, the areas of contact with the plastic or metal guides (such as under the bottom bracket) as well as all the points anchor.
Reminder: the cables and housings for derailleur and brake are not identical. They differ par the shape of the head and the diameter, so they are not interchangeable.
The cable can be made of steel or stainless steel: the first is the least expensive, the second has a better lifespan since it is more resistant to corrosion. In addition, to reduce friction and therefore improve the operation of your equipment, it can receive a layer of polymer a (usually called PTFE or Teflon®).
Depending on your practice (city, mountain biking, gravel, road), frequency of use and terrain, replace your cables (brake and derailleur) once par year at least. Cables and sheaths are wearing parts.
There is only one type of cable for derailleurs (unlike brake cables), no risk of error a priori, the differences mainly concern the conduit passages, rather at the level of the horizontal tube on mountain bikes, and rather at the level of the tube diagonal on road bikes.
In general, a mountain bike has 5 sections of sheaths in total, compared to 3 for the road bike, so you need to provide 10 sheath ends for a mountain bike and 6 for a road bike.
There are different types ofduct ends, metallic or plastic, waterproof or not. The metal ends are normally placed at the rear derailleur (last housing end before the rear derailleur).
End caps Shimano 2 grooves are standard tips, not waterproof, the 4 grooves are waterproof, this can be seen quite easily by looking through it, the hole in the waterproof tip is much smaller. The cable ends clip onto the end of the cables, once installation is complete, to prevent fraying.
To keep your bike's gears running smoothly and all gears shifting cleanly, not only the rear derailleur, shift lever and front derailleur, but also the derailleur cable, in particular its outer sheath, must be intact.
Derailleur cables and housings connect the shifters to the front and rear derailleurs. Also called speed cables and sheaths, they are a bit like the nervous system of the bike transmission ! Often neglected, their good condition and maintenance are nevertheless essential to ensure smooth and precise gear shifting.
The brake cables are often continuously sheathed, which limits infiltration of mud or dust under the sheath. Cutting pliers are very useful for cutting the sheaths without flattening them, which would then obstruct the passage of the cables.
Road and MTB brake cables have different ends, some are adapted to the covers of racing handlebars, others to the levers of flat handlebars. The metal sheath end is that of the road cable kit, it is not waterproof. The cable end piece is clamped at the end of a cable, after passing through the sheath, to prevent the cable from fraying.
Do not neglect the cable end, which prevents it from fraying. Crimped at the end of the cable using pliers, it often ends upar to fall. We will replace it advantageously par a lead or tin soldering point.
When the brake cables become frayed, it is urgent to replace them and change par the same occasion the brake sheath. A brake cable in poor condition reduces your braking quality and can be dangerous and unsafe for you. If there is slight rust, inspect their condition before each outing or replace them.
Choose a brake cable whose diameter and ends correspond to your bike. On the market, we find MTB bike cables, road bike cables, BMX brake cables. Some brands of brake housings are offered in different colors, such as blue, red, yellow or green.
- Road brake cable
- MTB brake cable
- BMX brake cable
- Cantilever brake cable.
Pour plus d'informations sur wheels and braking, click here
The derailleur cables have a diameter of 1,1 or 1,2 mm, smaller than that of the brake cables, which reach 1,6 mm. The difference is visible to the naked eye, but it takes a little practice to perceive it.
On the other hand, the cylindrical shape of a derailleur cable head is easy to distinguish from road or mountain bike brake cables. However, there are two slightly different standards. Derailleur cables Shimano are to the same standard as almost all brands. Alone Campagnolo requires specific derailleur cables.
The derailleur cables have a diameter of 1,1 or 1,2 mm, smaller than that of the brake cables, which reach 1,6 mm. The difference is visible to the naked eye, but it takes a little practice to perceive it.
On the other hand, the cylindrical shape of a derailleur cable head is easy to distinguish from road or mountain bike brake cables. However, there are two slightly different standards. Derailleur cables Shimano are to the same standard as almost all brands. Alone Campagnolo requires specific derailleur cables.
The sheaths guide the cables from the levers to the brakes and derailleurs in a smooth path to minimize friction. They must therefore be flexible, but very rigid in the axial plane in order to ensure powerful braking and precise gear changes.
The sheaths generally consist of a flexible plastic covering, a metal body and an internal Teflon tube to reduce friction with the heart. wheat. The metal body is either a winding of square wires in the case of brake sheaths (think of a compressed spring), or a twist of wires aligned along the axis of the sheath in the case of derailleur housings.
Inspect the sheaths for any splits or sudden bends that would significantly increase friction with the cable.
The standard cyclist should remember to replace cables and housings at least once.ar year, preferably in spring. When a cable is oxidized or the housing is filled with dirt, the shift lever or brake lever cannot pull the cable enough to perform the action smoothly. decision.
To extend the life of your components, equip your bike with steel or stainless steel cables with a polymer coating for your brakes and derailleurs. Install housings with waterproof ends to optimize the operation of your transmission.