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OK, this is naive question, but I have to be 200% sure :-)

If you compare the regular v-brake against parallel v-brakes as Avid Arch Rival 50:

enter image description here

the one thing which is always ignored is the way you can change the distance between pads. In the regular v-brakes you change the distance with the cable, more loose means more distance between pads.

But with parallel v-brake the distance is fixed, so loosening the cable does not change a thing, it just adds a dead cable section.

This influences the pads and the wheel rim you can select -- more fat pads or slightly wider rim and you have a problem.

The question is -- am I right with the fixed distance in such v-brakes?

UPDATE: fixed means -- there is some distance, predefined, and you can narrow it, but you cannot increase it. Let's say you are on the ride and you hit something hard with wheel. The wheel needs trueing. With regular v-brakes you just loose the cable to get home. With parallel v-brakes loosening cable does not help.

Photo comes from Avid Arch Rival 50 Review at GearReview

  • What do you mean by fixed. If the cable length makes no difference to the distance between the pads, how does squeezing the level (which shortens the cable) apply the brakes? I.e. adjustment of parallel brake sis exactly the same as any other V brake (Except you do it far less often). (The front 'arch' in the photo does change width - it has a centre pivot) – mattnz Sep 15 '14 at 2:07
  • @mattnz, updated. I didn't know how to describe it better -- you can of course narrow the distance, but you cannot make it bigger. I.e. the max width is predefined by the additional "horseshoe". In regular v-brake the width (distance) is just a matter of the cable. – greenoldman Sep 15 '14 at 6:19
  • Sure the horseshoe poses some slight reduction, but its effectively nearly as good - see img.photobucket.com/albums/0703/ashyRST/Bikes/IMG_1743.jpg for example. – Batman Sep 15 '14 at 7:03
  • I do not know these particular brakes, but it looks like you can make the gap bigger by playing with the spacers on the pads – mattnz Sep 15 '14 at 7:09
  • @batman, can you widen the distance, or the horseshoe will "block" the brake arms? – greenoldman Sep 15 '14 at 7:17
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iirc - the Arch Rival V-brakes are described as parallel because the brake block surfaces are always parallel to the rim braking surface at whatever distance from the rim. This in theory improves braking.

Other than this - they function the same as a normal V-brake in that the arms act as levers to apply the brake blocks to the rim surface.

Adjustment may be a bit more picky - in that as the cable is loosened and the braking arms move outward - it will raise the brake blocks to keep them parallel to the rim. Therefore, to get the pads further from the rim - you may have to slacken of significantly more tension than with traditional V-brakes. You may have to undo the cable entirely to slacken enough.

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All brake calipers have some spread limit. I don't see these to be different. When you're describing dead cable not affecting this distance, you kind of answer your own question. Most calipers stop at some point when spread apart. If you want to go beyond that limit, maybe different brakes will work better for you. The horseshoe is not affecting this, plus it can be removed without affecting functionality of the brakes.

  • Well if you call it "limit" when there is 1cm air between pad and rim at both sides... The question is looks more about "how much can you spread the pads in breaks like this arch". – Alexander Dec 26 '14 at 14:20
  • You are aware that the horseshoe is not a "brake booster " but part of the linkage? Have you run arch rivals without the horse shoe? – drRobertz Jan 8 '15 at 10:00
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In my experience, the arch rivals have a bit less "wiggle room" with cable tension released, than other brands but -- unless you want to run fat tires -- I think they're among the best V-brakes on the planet.

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