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So I am replacing the rear v brakes on my old Saracen ruff trax, callipers, cables and pads.

My questions is...

Unless I pull the brake cable tight through the calliper the pads do not get close enough to the wheel.

My concern is I’ve pulled the cable right through so that basically there is just the rubber boot and no cable (apart from cable outside the pinch bolt).

Is it an issue that inside the little bracket at the back the rubber boot gets squished up a bit.

Complete novice at maintenance if it wasn’t obvious

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    some photos would help with the description and fault finding. I would be looking for the little washers being all present and correct, and 90 degree angles between components (rim, pads, calliper arms). you can swap around the curved washers to achieve this as they come in two sizes
    – Swifty
    Mar 9, 2019 at 16:37

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If you haven't already or if they didn't come like this, the first thing to do in this scenario is switch the thicker pad spacers to be between the pad and the brake arm.

The optimal geometry is such that at the point in the arms' movement where the pads contact the rim, if you were to draw a triangle between the center of the brake pivots and the cable anchor as the points, you'd get either a right triangle or a slightly obtuse angle.

The reason is that the pad faces move in an arch. If you set up the brake like you have it, the pad is hitting the rim only once it's in the downwards part of that arch. This causes a squirmy, indeterminate brake feel, squirming noises, and the tendency for pads to dive off the rim. So you either want more like a rectangle than an A shape, or a slight V shape to give some room for pad wear before you're in the down part of the arch.

Pad spacers are your main tool to correct this. Put the thicker spacers inside and the thin ones outside. You can't always make it perfect, depending on if the post spacing is too wide or the rim too narrow.

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  • Thanks will give this a go and send photos
    – Matthew Stott
    Mar 9, 2019 at 17:09
  • So Is it possible to just move more spacers to between the pad and arm, knicking some from the outside?
    – Matthew Stott
    Mar 9, 2019 at 17:58
  • @MatthewStott that's a different question. "Perhaps" because the pad is now on a longer arm with more leverage and it could chatter easier. You'd have to try it out.
    – Criggie ♦
    Mar 9, 2019 at 22:53
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Thanks for the comments, in the end I just wasn’t lining up the pads correctly and did not have the brake cable pulled tight enough.

It took some fiddling to get the pads right but is fine now

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    Thank you for the completion - could you use Edit to expand this answer? What would you have wanted to tell yourself 3 days ago, to make this easier? Was it the order of spacers or the angles? You can also mark this as the accepted answer, because its what worked for you.
    – Criggie ♦
    Mar 13, 2019 at 3:09

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