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Whenever I remove the back tire and put it back on due to flats, I often need to readjust the rear caliper brakes because the wheel is not in the exact same position in terms of centering as before I took the tire off.

Is this an issue in the sense Im putting the wheel on slightly off-center from where I had the wheel previously or is this normal and there is some variance? Maybe need to move the brakes 2-4 millimeters.

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  • Do you have side-pull/dual-pivot rim brakes? (I mean those with a single bolt in the middle) Could it be that the bolt has become loose and the calipers move? You might need to tighten them up - I just checked for Shimano Tiagra and they recommend applying 8-10 Nm while the calipers are pressed against the rim for adjustment.
    – DoNuT
    Feb 28 at 7:14

3 Answers 3

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Are you installing the wheel with the bike upside down? I find that putting the wheel under the bike helps settle everything.

A few mm difference in angle at the rim is a tiny difference down by the axle, so jiggling things into place helps, as does clamping the rear brake lever on while tightening the QR.

Single-pivot calipers and brakes with "add-clearance" levers will move no matter what you do, so as part of reassembly make sure they're still centered.

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  • 1
    no the bike is upright
    – Lightsout
    Feb 28 at 2:14
  • 4
    Even if you change the wheel on a workstand (upright but with the weight in the wrong place), final tightening on the ground is often necessary. +1
    – Chris H
    Feb 28 at 7:07
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If you run your brakes really tight it seems to happen a lot. With a typical spacing at rest it doesn't seem like it should happen. But I'm finding the same, and when it happened before it was one of the first signs of a bent axle. I soon noticed that I needed to tighten up the rear hub cones - repeatedly.

So, especially if you also find your hub getting loose, you might want to check the axle is straight. That's a bit of a messy job, and as the bend can be very subtle, it means removing the cones and locknuts completely to test against a straightedge.

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  • "But I'm finding the same, and when it happened before it was one of the first signs of a bent axle." - Do you mean you experience this as well when nothing is wrong or only in a case where the axle was bent and replacing it fixed the issue?
    – WornChain
    Mar 1 at 21:47
  • @WornChain I plan to check my axle this weekend, because after fixing a puncture the brake is rubbing, without running the pads ridiculously close. It wasn't before I took the wheel off, but I did have to tighten the cones recently and they feel loose again.
    – Chris H
    Mar 1 at 22:04
  • ... While I'm talking about detecting it on discs, close-running rim brakes would experience a similar effect. I've never bent, only broken, an axle with rim brakes.
    – Chris H
    Mar 1 at 22:06
  • If you have loose cones then perhaps something is up. I just have this issue with no other signs of damage. Is pad clearance adjustable?
    – WornChain
    Mar 1 at 22:34
  • @WornChain on most brakes I've had you can adjust pad clearance, the exception being hydraulic discs. Repeatedly loosening cones implies a force that shouldn't be there, and brake rub when cornering is an early sign. Warped disc brake rotors are always worth checking for. They can be straightened but not usually perfectly - that's why I have a little more clearance in my pads than I'd like, which in turn means adjusting them more often
    – Chris H
    Mar 2 at 8:27
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I experience the same issue, so I've assumed it to be normal with QR(quick release)+disc brakes even though 2-4 mm sounds a bit exaggerated (there is only so much space it can be off-set and still fit in between the pads). It is more of a question of getting rubbing pads or not.

It applies to both front and rear, and sometimes I solve the issue by releasing the QR, making my best effort to get the axle into the dropout and tightening while the bike is perfectly straight and under a gentle downwards pressure.

On the front wheel I can see the centering of the rotor/disc between the pads before/while tightening which often makes it possible to get it perfect on the first try and avoid having to adjust the caliper position afterwards. One can also see from the relative pad/disc position that it is easy to mount the wheel in slightly different positions which is enough to cause rubbing if you don't take care.

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