Bicycles Asked on February 26, 2021
Logic tells me no, but if I refit my disc brake wheel and the disc is rubbing slightly on the caliper, if I undo the QR lever, tighten the nut on the other side clockwise and loosen the QR the same amount anticlockwise, then push closed the QR lever again it can correct the rubbing, i.e. it shifts the wheel slightly to one side.
Am I imagining it, or is that a recognised thing of how QR mechanisms work?
I've seen this, it's real. The physics of what actually happens to the axle under QR compression are a little mysterious, to me at least. Standard axles get slightly bowed, and that could end up having some effect on the alignment of the hub shell. One could also contrive a situation where dropout misalignment allows variance in QR force to cause this effect, especially combined with an external cam QR and/or especially if the QR is in poor condition or unlubricated. And, since QR compression affects bearing preload, it could also be a simple case of the rub happening when it's under-tightened such that there's play in the hub, which would usually suggest a hub that wasn't tight enough to begin with. It's also possible to imagine differing QR force causing a difference in how the left locknut meshes into the paint and metal of the dropout.
When I've seen it, the real problem is the pad centering. In other words, even when you have the QR so it's not rubbing, it's only barely not rubbing because the rotor is too close to the pad. If you want to avoid rubbing when the bike is ridden you need more of a buffer gap than that anyway to accommodate flex.
Correct answer by Nathan Knutson on February 26, 2021
It is possible that when you put in your wheel into the drops you are not seating it all the way before tightening the QR.
This can lead to the wheel being slightly off angle that would lead to rubbing.
The fix for this is some people will install wheels when the bike is on the ground to prevent this or alternatively you need to apply pressure into the drops as you close the quick release when the bike is firmly in a stand.
I tend to use the second approach as often when I remove the wheel the bike is in a work stand. I have found that once I reach the normal tension prior to closing the QR usually snug and such that when I close the QR it leaves an impression in my palm, that any alignment issues usually have to do with not getting the wheel all the way into the drops.
Another possibility, which I do not think is the case is your wheels could be out of true and that is fixed by adjusting spoke tension.
Answered by Tude Productions on February 26, 2021
Get help from others!
Recent Questions
Recent Answers
© 2024 TransWikia.com. All rights reserved. Sites we Love: PCI Database, UKBizDB, Menu Kuliner, Sharing RPP