# Disc brakes rubbing after tyre change



## lulubel (13 Nov 2012)

I put the new tyres on my bike today.

Usual method - flipped it upside-down, removed the wheels, changed the tyres, replaced the wheels, and put it up the right way again. The same method as I used when I had to change a tube out on the trails.

When I stood it back up, I noticed the front wheel wasn't spinning freely. The brakes are rubbing slightly. I tried removing the wheel and replacing it again in case it wasn't in the dropouts properly, but that hasn't fixed it. I tried squeezing and releasing the brake lever a few times with the bike in the upright position - no idea why I thought that might help! - but that hasn't fixed it either. I've looked for a way of adjusting the brakes, but can't see anything obvious.

I'd like to ride the bike tomorrow, but don't particularly want to ride it with the brakes rubbing because:
a - it will be hard work
b - it probably won't do much for the life of the brakes

The brakes are Shimano BR-M505.


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## bjellys (13 Nov 2012)

Make sure that the wheel is aligned properly & then try slackening the bolts that hold the caliper on, then hold the brake on while you do the bolts up again.I also find if I have the skewers to tight it makes my wheel bind.


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## Motozulu (13 Nov 2012)

When I put my brand new pads in they were a bit tight too - spun the wheel and it was dragging - I then loosened the bolts fixing the brakes to the frame, spun it again and clamped the brakes on hard.....tightened bolts without releasing brake to centre them..tried that? otherwise a little fine sandpaper on the pads to shave them down a bit?


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## Motozulu (13 Nov 2012)

bjelly - snap!


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## mcshroom (13 Nov 2012)

Maybe the wheel has a slight dish on it. Try flipping the front wheel over and refitting to see if that makes any difference. 

Also have you checked you haven't knocked the calliper while you were refitting the wheel?


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## Andy_R (13 Nov 2012)

mcshroom said:


> Maybe the wheel has a slight dish on it. Try flipping the front wheel over and refitting to see if that makes any difference.
> 
> Also have you checked you haven't knocked the calliper while you were refitting the wheel?


Disc brakes Mc....cant"flip" the wheel, disc will be on the wrong side!....agree with Bjelly about the skewers, I used to have the same problem with my br775s.


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## mcshroom (13 Nov 2012)

Ah, I forget about these weird new-fangled disk thingys.


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## lulubel (13 Nov 2012)

bjellys said:


> I also find if I have the skewers to tight it makes my wheel bind.


 


Andy_R said:


> agree with Bjelly about the skewers, I used to have the same problem with my br775s.


 
I'll have a look when I can get up - have a warm cat on my lap at the moment, and I don't feel like moving! That sounds most likely, knowing me, because I do have a tendency to do everything as tight as possible "just in case".


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## Andy_R (13 Nov 2012)

mcshroom said:


> Ah, I forget about these weird new-fangled disk thingys.


I know, round things on bikes, whatever next...............


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## compo (13 Nov 2012)

I always set the wheel back in the dropouts then apply the brake firmly before and whilst I do up the QR skewer. This aligns the disc with the pads.


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## mickle (13 Nov 2012)

Its not straight in the dropouts. With the bike upright - ie not leaning against anything (and definitely NOT turning the bike upside down and without holding the brake lever) release the qr lever and do it back up again. The wheel hub will settle in the dropouts. 

Tada.


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## mickle (13 Nov 2012)

compo said:


> I always set the wheel back in the dropouts then apply the brake firmly before and whilst I do up the QR skewer. This aligns the disc with the pads.


No it doesnt.


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## lulubel (13 Nov 2012)

mickle said:


> Its not straight in the dropouts. With the bike upright - ie not leaning against anything (and definitely NOT turning the bike upside down and without holding the brake lever) release the qr lever and do it back up again. The wheel hub will settle in the dropouts.


 
That was the first thing I tried, and it didn't solve the problem. I suspect it's as others said, and I've done the QR up too tight.


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## Motozulu (13 Nov 2012)

If not Lulu try the loosening the brake caliper bolts trick - holding the brake on and then re-tightening em, I believe this is how you centre the brakes - worked for me.


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## lulubel (13 Nov 2012)

I've had another fiddle with it, and I'm beginning to suspect they've always rubbed slightly, but I've never noticed it before. The only reason I noticed it today was because the brakes squeaked when the wheel moved slightly. They only started squeaking towards the end of my last ride.

As part of my fiddling, I turned it upside-down, and pulled the brake lever with the QR open. The pads pushed the disc quite a long way outwards, and it also seems to be the inner pad that's rubbing. Will loosening the pads and tightening them again with the brakes on align them properly?

And on the subject of squeaking brakes, what's the best way to deal with that? I suspect they've got a coating of dust. I usually clean my bikes (including braking rims and rim brakes) with baby wipes, but I've read somewhere that they're not good to use on disc brakes.


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## Motozulu (13 Nov 2012)

I use proper disc brake cleaning spray - as you say baby buds around the pistons soaked in the stuff - they are proper black afterwards  take the pads out and clean em - if they are really crudded up I give them a very light sanding with fine guage wet an dry sandpaper then pop em back in - sweet.
It does sound to me though that your brakes just want re-centreing - just loosen the caliper fixing bolts - brake on and tighten.


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## lulubel (13 Nov 2012)

Motozulu said:


> It does sound to me though that your brakes just want re-centreing


 
I'll have to have a go at that, then, although I think I'll just ride it tomorrow and mess with it on Thursday, or I'll probably end up not having time to ride it!


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## potsy (13 Nov 2012)

Squeaky disc brakes are my early warning to peds on my off road commute, I'll never be able to sneak up on anyone 
I find the slightest bit of puddle or dirt starts to make the pads sound like they are rubbing, I suppose cleaning is the answer, might try it one day


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## Motozulu (13 Nov 2012)

I had the same problem as you Lulubel and went on bikeradar site where they have these ace tutorials on youtube - see if I can find it again.


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## Motozulu (13 Nov 2012)

Try this...
http://www.bikeradar.com/gear/article/video-workshop-how-to-align-your-disc-brake-calipers-32591/


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## lulubel (13 Nov 2012)

Motozulu said:


> Try this...
> http://www.bikeradar.com/gear/article/video-workshop-how-to-align-your-disc-brake-calipers-32591/


 
That's great, thanks. And it looks simple enough for a first go at disc brake maintenance.


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## Motozulu (13 Nov 2012)

No probs lulubel - me and you are about at the same stage...Huzzaaaah for youtube!


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## Cubist (14 Nov 2012)

Re- centering brakes is a sort of pre-ride check ... takes about 10 seconds per brake, and with the old Hayes they needed doing every ride. New Shimano are "servo-wave" which means the pads are set with much greater clearance and never seem to rub. Avid Elixirs on the Boardman were NEVER set to my fastidious liking. 

Don't fret about a bit of dust, just leave it. If you keep cleaning rotors and pads you'll eventually contaminate them. I spray and wipe the rotors with brake cleaner and a clean rag just to get any shampoo off them


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## GrumpyGregry (14 Nov 2012)

all sorts of disc brakes do this for all sorts of reasons.you get used to it. just ride the bike, a bit of rub will soon disappear after a few brake applications.


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## Motozulu (14 Nov 2012)

Fair enough cubist but this time of year my pads are continually clogged with cack - I do follow the dog 3 times a week - I'll probably just give them a hint of sandpaper now and again just to get the grit off - I see what you mean about continually soaking them with brake cleaner.


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## Christopher (14 Nov 2012)

I had exactly the same prroblem as the OP, and I had an Avid BB5 mechanical brake and it would take 5 to 20 minutes to get it right after taking the front wheel out. Usually I had to loosen the caliper bolts and adjust it manually. Pads had to be incredibly close for the brake to work at all. I gave the caliper away to a charity and have gone back to rim brakes.


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## MrJamie (14 Nov 2012)

I had some trouble when I installed my Avid BB7s recently after following numerous online guides with different techniques and advice. The key thing with the BB7s seems to be not just getting the caliper aligned straight which is easy, but getting it aligned right horizontally (ie. the correct distance from the pads). I don't know about other disc brakes, but on the BB7 only the outboard pad moves in and pushes the rotor against the inboard pad, so getting the rotor the right distance from the static inboard pad is hugely important. So about my 5th attempt at aligning the caliper it went from skimming the pad, very loud squealing in the wet and a juddery brake feel, to sharp smooth and quiet braking in the wet, I couldnt believe the difference it made when I got it right, so glad i didn't just decide to put up with it.


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## lulubel (14 Nov 2012)

Thanks, guys. It's all sorted. I adjusted the calipers and they're now lovely. No rubbing and no squealing either (which is a bit of a shame really because it drowned out my bad singing). It wasn't quite as quick as in the video, but it only took me about 10 minutes.


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## compo (14 Nov 2012)

I can't speak for other people but when I remove and refit my front or rear wheel the disc always rubs slightly on the disc. All I do is pull my brake on (with the bike upright) and then do up the skewer and the rubbing stops and the brakes work perfectly. I accept what Mickle says above that I may not be correct in my understanding of how this works but it always does for me. All this assumes that nothing in the caliper has been disturbed, only the removal of the wheel.
When adjusting the pads I use the Shimano method with a .3mm feeler gauge. Set the anvil first then the moving pad. Works every time. I have Shimano mechanical discs so maybe they are easier to set up than hydraulic systems, I don't know. It seems crazy to me if you have to reset the caliper every time you take a wheel out.


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## lulubel (14 Nov 2012)

compo said:


> All I do is pull my brake on (with the bike upright) and then do up the skewer and the rubbing stops and the brakes work perfectly
> 
> It seems crazy to me if you have to reset the caliper every time you take a wheel out.


 
My guess is it happens because the pads are so close to the disc (compared to rim brakes) that it only needs the QR skewer to be a tiny bit misaligned in the dropouts to cause them to rub.

As long as I don't have to take the wheels on and off too often, I don't mind re-aligning them. It didn't take me long.


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## Peteaud (14 Nov 2012)

Avid Elixir on my MTB do this if the bike is flipped or transported on its side.

I just re center them.


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