V Brake cables life ?

[Mike777]

Hi all

Just wondered how long brake cables last for .....

I ride my bike every day and have clocked up about 1000 miles since I brought it in Nov 2014

I have already replaced the rear pads and adjusted the rear cable a couple of times as the pads have worn.......so just wondered about knowing when to replace the cable or is there a period or mileage that people would use to know when to replace.

Brakes are Shimano Deore BL-T610 V-Brakes

Also are all cables standard or what would people recommend.

Many thanks for time

Regards

Mike

[pwa]

Replace when you notice something is wrong with the way they are working. Cables that are sliding smoothly will not be frayed and in danger of failing. Cables that seem to catch are likely to have a frayed part and need changing asap.

[Brucey]

cables usually fail wherever they are repeatedly flexed. In a V brake this usually happens next to the pinch bolt on the brake arm. Once every few months slide the concertina boot back and inspect this region carefully. Any broken strands mean the cable is weakened and may (in time) fail.

Cables can fail in the lever through flexing or through chafing if a bare part of the cable run rubs anywhere. In time the plastic liner in the 'noodle' (and indeed the remainder of the cable housing) will wear through too and this will reduce braking efficiency.

I think you would be unlucky to have any cable problems within six months or so even in heavy daily use.

For new cables, I suggest stainless steel inners, lubricated with a little grease that is known to be compatible with the polymer liner in the cable housing.

cheers

[Mike777]

Many thanks for the informative replies.

Been looking to buy a replacement cable for my model BL-T610 but can not find reference to the model number or a cable stating it's for that model.

On that basis are all cable the same in standard diameter and then different lengths for front and back ?

Many thanks again

Mike

[beardy]

I only ever buy stainless the galvanised steel ones rust and that causes friction in the cables.

They come for MTB type levers with a barrel nipple or road type levers with a pear type nipple.
You can get universal ones with a different nipple at each end. You have to cut the "wrong" nipple off.
Personally I dont use them as cut cables fray and I prefer to roll up the uncut length of spare cable near the pinch bolt then I can still rethread the cable through the inner at a later date, cut ends can give problems doing that.

If you have a very large frame and bars needing long outer cables (like high butterflies) you may have to check the length of the cables.
At the rear, some are 1900mm and others 2000mm and others 2100mm.
1900 is more than long enough for most people.

[mjr]

Cut cables don't fray if you crimp an end cap onto them.

[gregoryoftours]

Cut cables don't fray if you crimp an end cap onto them.

Even that splays the strands a little where you crimp it unless you cut that bit off if you want to re-thread it. A good way of avoiding this is to use narrow electrical heat-shrink instead which is removable and which doesn't crush the cable in any way. Even still, re-threading cables when the end has been cut you always stand a chance of catching the strands and scoring the plastic lining of the outer on it's way through - the chances of this are minimized but not eliminated by twisting the cable or housing in the direction that goes with the winding of the inner cable strands as you push the cable through.

With buying new inner cables, yes go stainless every time.

[bainbridge]

A little dab of superglue seals the cut end, it wont fray and you can easily re thread it if need be.

I keep one spare rear brake cable and one spare gear cable in my pannier, all prepared and greased, wrapped in clingfilm.

[[XAP]Bob]

They can still fray at pinch bolts and other tight radius bends. I'm also in the heatshrink club for cable ends, those little ferrules are guaranteed to fray the cable to start...

[Des49]

Agree cable end caps can start fraying, if I use them I try not to crimp them too hard and do so on the open end to be as far from the cable end.

I have always prefered soldered cable ends. However ran out of the right flux and cannot seem to get any. I prefer stainless cables and many years ago someone at a workshop put a small amount of flux in a jam jar for me. This has now run out and I cannot source any more. Even the internet doesn't reveal a supplier to me. May be it's too corrosive for sale to the public?

Does anyone know where I can get some stainless flux in a small pot?

[531colin]

Axminster tools were a good source of materials for silver soldering stainless, last time I looked

[Brucey]

you can soft solder stainless steel provided you use a reasonably strong acid to clean the parts with. IIRC phosphoric acid should work OK, but getting it to 'wet' through the cable thickness really well is kind of tricky. The problem then is that the soft solder itself will corrode quickly in service unless it is well coated in grease etc.

So I prefer to silver-braze (silver solder) stainless steel cable ends, if I think I'll ever have to rethread them through the housing. Special flux required; I use JM Easiflo for stainless (which IIRC comes in a tub with a purple label).

However I've almost given up doing this with gear cables these days because they are prone to fray in the shifter or the mech at about the same time you might want to pull them out of the cable housing to clean/relube them anyway.

cheers

[Des49]

Axminster tools were a good source of materials for silver soldering stainless, last time I looked

Thanks will take a look.

So I prefer to silver-braze (silver solder) stainless steel cable ends, if I think I'll ever have to rethread them through the housing. Special flux required; I use JM Easiflo for stainless (which IIRC comes in a tub with a purple label).

Is this possible with a good soldering iron, or is stronger heat needed?

[Brucey]

what most people call 'silver solder' (or silver braze) melts at around 700C, and that is what I'd suggest you use. However there are some other materials with which it is possible to get confused eg

-silver bearing soft solder (typically ~3% silver, 250C melting point) (stronger than conventional soft solder)

- medium temperature silver braze metal ( melting point ~450C).

The latter material is stronger than soft solder but nothing like as strong as conventional sliver braze metal. JM used to make this stuff but I don't know if they still do or not.

cheers

[Des49]

Thanks Brucey.

Probably not a job for my old soldering iron then.