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I am referring to the bolt, in the V-brake, that holds the cable on the opposite side of the noodle (as in this question). Yesterday I loosened that bolt to take the wheel off (I learned later that there is an easier way, it is enough to take out the noodle), and even though I fastened it again after putting the wheel back, I don't know how to check if I did it properly enough, and that the cable won't just come loose while I ride and cause the brake to stop working. Of course, I tried the brakes a couple of times, even while circling on the bike, and they seemed ok. But the question remains:

Is there a way to make sure that the cable will never come off from under the bolt? I.e., that 1.) it seats deep enough (and with enough of its surface *) under the bolt AND 2.) that the bolt is tight enough?

* Another question I asked myself is: why is (was) the cable guided only on the top and side of the bolt? Why not give it a full turn, so that it has more surface under the bolt? Would the only problem be, that then it would be sticking upwards, instead of downwards?

N.B.: Even though in this case I unfastened and fastened it (although it was not necessary to do so), the question could apply to many other scenarios (installing new brakes, making sure a newly bought bike, or a bike unused for a long time are safe, ...)

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  • 1
    You can use a torque wrench set to 6–8Nm if you want to make sure. It takes surprisingly little torque, even 3Nm or so would be enough.
    – Michael
    Jul 27 '20 at 12:07
  • 1
    A reasonable torque suffices. Do not make a pancake of that cable. A reasonable force with a multitool hex key is enough.
    – Vladimir F
    Jul 27 '20 at 13:23
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    @Attilio If you really squish it, it will be more prone to fraying, especially if it has to be loosened and repositioned later on. Jul 27 '20 at 17:27
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    @MaplePanda I agree, but that's what the OP is worried about, and IME bolts loaded like that don't work loose if sensibly tight
    – Chris H
    Jul 28 '20 at 20:06
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    @Chris H And to the OP, what I’m trying to say is “as long as the bolt is tight, the cable will be secure”.
    – MaplePanda
    Jul 28 '20 at 21:33
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To check the holding ability of the screw, while stationary, squeeze the lever as hard as you can and see if the cable anchor retains the cable. There should not be enough slack to allow the brake lever to contact the handgrip. The reason for not wrapping the cable around the screw is the cable strands are more likely to break from the tight bending. It also would make it difficult to reposition the cable to adjust for wear or pad replacement.

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  • > To check the holding ability of the screw, while stationary, squeeze the lever as hard as you can and see if the cable anchor retains the cable. Yeah, basically this is what I did already. The question is: is there something else, that one can do? (To be sure that it would not come loose say at the 15th squeeze while riding downhill?) Or is this really the most that is possible to do reasonably?
    – Attilio
    Jul 27 '20 at 12:24
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    I’d be more concerned about the cable housing failing somewhere (e.g. slipping through cable stops, maybe because you forgot a housing end cap)) than the cable slipping from under a properly installed clamp bolt. Just give the brakes a few strong squeezes with both hands, if there are no strange noises and no change in behaviour it should be fine.
    – Michael
    Jul 27 '20 at 12:35
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    +1. I safety check several times like this in series. Jul 27 '20 at 17:27
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    Concur - it should be habit to flex both brakes when you get the bike out for a ride, part of the most basic safety check just before riding.
    – Criggie
    Jul 27 '20 at 19:39
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    As @Criggie says. I've kept a bike somewhere at high risk of vandalism and am a little paranoid about brakes because of my accident. This means I tend to test the brakes as I walk the bike, and then again as I start to ride, before I get going quickly. Other precautions for working on brakes include only doing significant work on one brake at a time, so you have the other even if you made a silly mistake, and making it obvious at the lever when the brake is out of use (and old helmet strap clipped round the lever and grip is what I use)
    – Chris H
    Jul 28 '20 at 10:01

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