Campy disc brakes

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audiojan
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by audiojan

Is there any way to adjust the pad width? The calipers are perfectly aligned yet there’s some very light touching intermittently of the pads on the rotors. I bet the rotors are not perfect (that would surprise me) so I’m thinking it must be a way to adjust the calipers to accommodate this slight out of true
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Mr.Gib
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by Mr.Gib

Sorry, never worked with Campy calipers but if I have a disc that is a bit out of true, I just note the spot where it rubs and then rotate the wheel so I can get my hands on that spot, and I give it a good tug (or push depending on which side is rubbing). Works every time.
wheelsONfire wrote: When we ride disc brakes the whole deal of braking is just like a leaving a fart. It happens and then it's over. Nothing planned and nothing to get nervous for.

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corky
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by corky

I thought Campagnolo had a bite point adjustment? Does this not adjust the gap? Maybe it just changes lever throw.?

This inadjustment of pad rotor gap is a fundamental design fault of discs but is so rarely mentioned by reviewers manufacturers and even users.
Relying on the deformation action of the seals and capillary action of the brake fluid to retract pads means the gap has to be small. Which leads to rubbing. Which leads me not to want discs......

wingguy
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by wingguy

Pads only go as far out as they go. If they’re not all the way out, maybe because the lever has been part pulled without a disc in, you want a calliper press to push them back out. Or wiggle a flat bladed knife around in there if you’re careful.

Then if the rotor isn’t true you want a truing tool to very gently bend back the bits that are off. It does make it easier to get right than using hands, plus you’re at less risk of getting oily crap on the rotors.

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Miller
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by Miller

audiojan wrote:
Sun Apr 07, 2019 10:18 pm
Is there any way to adjust the pad width?
No, I don't think there is. I'm running two bikes now with Campag discs so I do have experience with them. As someone says above, the pads go out as far as they go and they settle down pretty close to the rotor. That said, mine do run quietly other than after hard braking or if they get splashed with gritty water.

In your case I'd be fiddling with precise caliper location, loosening the bolts to revise the caliper position.

morrisond
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by morrisond

I think they introduced new Pads and a stronger return spring with EPS that are backwards compatible with older Camoy Calipers.

You could try those.

But have you ridden it yet? Very slight noises go away ususally just by going out and hammering on the brakes a few times. That works for almost any disc brake and Camy as well.

In terms of operation I'm incredibly impressed by Campy brakes - very little stroke before they start producing great power and easy to modulate.

With Shimano and SRAM I could take or leave there Hydro's (I didb't like the free stroke before they bit) as not much better than Rim brakes - with Campy though I'll never buy enough Rim frame.

RyanH
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by RyanH

I had the same problem with my setup that I never ended up resolving. Most likely you need to face the mounts.

bm0p700f
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by bm0p700f

Yes face the mounts.

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Dan Gerous
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by Dan Gerous

Rotors, even new, are often not perfectly true and because the gaps are so small, it doesn't take much warp of the rotor to rub a pad... I would do as Mr.Gib suggested and true the rotor, pretty common fix to have to do, not too hard either, just go easy at first, better slowly but surely than bending it too far. In my experience though, one piece steel rotors are easier to fix, they tend to stay how you bend them for good while rotors with alloy carriers often bend back to their original position after some use, depends if only the steel track is off or if the problem is in a less than perfect alloy part I think. But usually you can still get it close enough to perfect that you can align the caliper so the rotor clears both brake pads.

bm0p700f
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by bm0p700f

sounds like your advocating bending the rotor to accomodate the mounts assuming the mounts are fine and its the rotor thats bent. the first thing you do is face the mounts, then true the rotor if needed. What do I know, I am only a mechanic.

Assumptions is how you make an issue worse. That the best bit of advise anyone can give.

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Dan Gerous
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by Dan Gerous

I'm advocating 'un-bending' the rotors! :mrgreen:

Wouldn't the rub be always there and not intermittent on each wheel revolution if the mounts were not square? That's what lead me to believe it's the rotors...

I haven't seen a frameset with the mounts not faced after being painted in a long time while I'd say 50% of new rotors I have seen are not perfectly straight... but I'm not a full time mechanic, all the bikes I have built are from the same brand so I don't have experience across a wide range.

by Weenie


c60rider
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by c60rider

I have this exact problem with my new Ribble frameset on the front brakes. I'm building it up myself and they were faced to some degree but even just resting the mount you could see there was still some paint encroachment onto the faced area. My local bike shop (a Colnago dealer amongst others) said they just use a file if there's any issues!! :noidea:

I remember speaking with Graeme FK a year ago and he said how much Campagnolo had worked on the brakes to ensure the discs were pretty much as straight as it's possible to get, I can't remember the exact tolerance he said, but it's interesting to note that they're actually made in Taiwan. Campag regulars will now their stuff is made in either Italy or Romania. So I don't know who's making those for them. So I don't believe it will be the disc that's at fault. I attempted to get the best fit by filing off the little bit of paint but the front has remained a nightmare to get right. Just taking the front wheel out and back in can cause it to catch and just a fraction extra turn on the through bolt can have an effect. I've concluded it's totally down to the faces and I decided to pull the trigger on the Park tool as I couldn't find anyone locally to do it. If a job needs doing right then I tend to have to do it myself. I had it delivered today so I'll be having a play with that tomorrow and can feed back my findings. But I'm pretty confident it's poor facing of the mounts by Ribble. Or their frame supplier.

The rear brake has been much better and the way that's been faced off has no paint encroaching but they definitely aren't flat/parallel somewhere so it will be interesting how that looks when I compare them both using the Park tool.

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