Disc rub with new wheels

alim0229

Hi there

I recently purchased some new lightweight alloy wheels for my road bike. Having fitted the front wheel, there is now a rub on the disc. Furthermore, if I tighten up the thru axle to a “normal“ level then there is a considerable rub and resistance to the wheel. The wheel will rotate more easily if the thru axle is kept fairly loose. I have tried to reposition the caliper by loosening the bolt, pressing the brake and then tightening again. I have also pushed back the pistons. Neither of these have helped.

The bike is fairly new, having done very few miles hence I cannot see how the disc can be warped. Furthermore, there were no rub issues with the previous wheels and same discs

Not sure how to solve this. Any advice please?

zefs

If there is rub when the pistons/pads are moved all the way out it could be an issue with the wheel setup. Is it a 6bolt or center lock rotor?
Might worth uploading a photo and posting the model of bike/wheel combination here.

paulbnix

Is the rub constant or intermittent?
Intermittent implies bent rotor, constant implies offset caliper.
If the caliper is offset you should be able to see it and in this case loosen the caliper bolts and physically shift the caliper until the rotor is central, then apply brakes and tighten the bolts.

cycleclinic

Recenter the caliper. This normal when fitting different wheels.

alim0229

paulbnix wrote:

Is the rub constant or intermittent?
Intermittent implies bent rotor, constant implies offset caliper.
If the caliper is offset you should be able to see it and in this case loosen the caliper bolts and physically shift the caliper until the rotor is central, then apply brakes and tighten the bolts.

If thru axle tightened to a normal tightness then rubbing more or less constant. I’ve tried to recently - just to confirm I am using correct technique - loosen bolts, press brake then tighten bolts.

This doesn’t seem to help really

The discs are Shimano Center lock system

Not what else I can do

Wheels are brand new

veronese68

I’m guessing they are cable brakes, hydraulic will sort themselves out to a limited extent. Try centring the calipers by eye.

alim0229

Veronese68 wrote:

I’m guessing they are cable brakes, hydraulic will sort themselves out to a limited extent. Try centring the calipers by eye.

The brakes are Shimano hydraulic not cable

Is there any washer that goes between the lock ring and disc - I am presently putting lock ring straight onto the disc?

Do I just ride and hope it will bed in

veronese68

A hydraulic brake should compensate for minor alignment issues as the fluid can move from one side of the caliper to the other.
As above is the rub constant or intermittent as you turn the wheel? If constant it’s caliper alignment. Loosen the caliper and line it up by eye with the wheel in and fastened properly. If it’s intermittent with every revolution you may have bent the disc a little. You may be able to bend it back carefully if so.

abba

alim0229 wrote:

paulbnix wrote:

I’ve tried to recently - just to confirm I am using correct technique - loosen bolts, press brake then tighten bolts.

You can't prevent the calliper from moving by pressing the brake.
Bolts should be tightened very carefully.
Spin the wheel then center calliper and while it rotates try to tighten the bolts.

svetty

Unfortunately there is no obvious source of shims for Centrelock rotors in Europe. November bikes in the US sells them in the states but doesn't export.
You can enlarge the hole on 1mm Shimano cassette spacers to act as shims but this is then +/- 1mm when thinner shims are generally necessary.
Re-centering the caller usually works but it's a ballache doing this every time you swap wheels.

Vino'sGhost

But but but discs are no problem and a massive improvement how can this be?...

kajjal

There may be too much fluid in the brake. If there is too much fluid the gap between disc and pad can be very small making it hard or in some cases impossible to get the wheel spinning without any rubbing.

Also check nothing has got in behind the brake blocks like a small stone as this will force the pads onto the disc.

To check if a disc is warped spin the wheel slowly and look down the calliper so you can see the gap between pad and disc.

paulbnix

Loosen bolts, press brake and tighten bolts is supposed to be the method but it doesn’t always work.
You have to align the caliper after loosening the bolts.

I struggled to stop rub after changing wheels until I realised there was a bit of muck on the inside of one of the calipers. So a good clean might help.

Nick Payne

Maybe there's insufficient sideways adjustment in the bolt holes holding the caliper in place. I have one disc brake bike with an IS2000 mount on the fork, and using an IS2000 to post mount adapter to which the post mount caliper is attached. When I swapped wheels on that bike recently, there wasn't sufficient sideways adjustment to prevent the rotor rubbing on the brake pad. I had to grind about 0.5mm off the mounting face of the adapter to be able to get rid of the brake rub.

Livewire

Remove pads, push pistons back carefully, loosen caliper bolts, centre the calliper by eye over the disc, tighten bolts making sure the caliper is still centered over the disc, re fit pads, pump brake and away you go.

schlepcycling

I used a tip I saw in this GCN video (first couple of minutes) https://www.youtube.com/watch?v=gQ_oIAPuQR8 . Remove the wheel, then fold something like a business card over the rotor and then re-install the wheel, loosen the caliper, press the brake and tighten the caliper back up.

keef66

It sounds like just applying the brake isn't moving the caliper (enough). Loosen the bolts and move it by hand till you get no rubbing. Then apply the brake and tighten the bolts.

Vino'sGhost

have you got the front and rear rotors in the right order?

are you pulling the lever?

alim0229

Ok all got solved. New wheels had end cap missing on side hence the issue. All sorted now. Thanks all for your help particularly the suggestions if constant rub likely wheel issue which is what it was

Scoob84

Vino'sGhost wrote:

But but but discs are no problem and a massive improvement how can this be?...

I foolishly bought into disc brakes being the the future and was attracted to them by the apparent low maintenance aspect to them. After having both my caliper brake bikes stolen, i replaced with disc braked bikes and have had no end of braking issues with both. I too get brake rub on both bikes when out of the saddle and putting an effort in. My 4 grand canyon now sounds like i'm sharpening a knife even when just cruising along. Its driving me mad.

veronese68

Scoob84 wrote:

My 4 grand canyon now sounds like i'm sharpening a knife even when just cruising along. Its driving me mad.

That would drive me mad too, it should be possible to fix it. My 4 year old bitsa Kinesis built on the cheap has never done that, in that time it's had two different sets of brakes and wheels, a variety of brake pads and been ridden in all conditions. They sometimes squeal when it's wet of course, unfortunately never when I want them to as some idiot has stepped out in front of me.

kajjal

Scoob84 wrote:

Vino'sGhost wrote:

But but but discs are no problem and a massive improvement how can this be?...

I foolishly bought into disc brakes being the the future and was attracted to them by the apparent low maintenance aspect to them. After having both my caliper brake bikes stolen, i replaced with disc braked bikes and have had no end of braking issues with both. I too get brake rub on both bikes when out of the saddle and putting an effort in. My 4 grand canyon now sounds like i'm sharpening a knife even when just cruising along. Its driving me mad.

Are the wheels boltthru rather than QR ?

If they are then the only way you could get rub is if the fork or frame is flexing a lot. Quality hydraulic disc brakes should not rub, I have three bikes with them on and once set up properly only a bent Rotor caused me problems with rubbing.

hopkinb

Scoob84 wrote:

My 4 grand canyon now sounds like i'm sharpening a knife even when just cruising along. Its driving me mad.

That's just a badly set up brake. As if you'd left a pad rubbing on the rim of a rim-braked bike and refused to do anything about it. Take the pads out, push the pistons all the way back into their housing, put the pads back in, loosen the caliper bolts, squeeze on the brake, tighten the caliper bolts. If that doesn't do it, then 5 mins aligning the caliper by eye will do it, and you'll be rub free until you change the wheel or have to replace the pads. Unless you have a bent rotor from a crash or something. Otherwise your 4 grand canyon is flexy like wet spaghetti, or your raw powaaah is causing a 4 grand bike to flex while cruising.

Scoob84

hopkinb wrote:

Scoob84 wrote:

My 4 grand canyon now sounds like i'm sharpening a knife even when just cruising along. Its driving me mad.

That's just a badly set up brake. As if you'd left a pad rubbing on the rim of a rim-braked bike and refused to do anything about it. Take the pads out, push the pistons all the way back into their housing, put the pads back in, loosen the caliper bolts, squeeze on the brake, tighten the caliper bolts. If that doesn't do it, then 5 mins aligning the caliper by eye will do it, and you'll be rub free until you change the wheel or have to replace the pads. Unless you have a bent rotor from a crash or something. Otherwise your 4 grand canyon is flexy like wet spaghetti, or your raw powaaah is causing a 4 grand bike to flex while cruising.

We can definitely rule out raw powaaah as a theory. Although i'm carrying some saggy bits, i'm under 80kg so we can probably rule my weight out of this.

I've tried lining us the brake as you describe a fair few times, to the point i'm now starting to round off the bolts. Admittedly i haven't tried poking the pads back in yet.

Annoyingly on the Canyon, the rub occurs at a certain point of the wheel revolution which suggests either a slight buckling or warping on the disc or maybe even a burr on the edge. But i can't see this by eye, and i can't imagine its damaged because its had an easy life since i bought it (new) and have barely ridden it to my shame. I've reached the point where i'll give it to a professional mechanic to fix.

But even on my genesis (mechanical discs and QR) i get a bit of rub when out of the saddle, but its fine when sat in it.

haydenm

Scoob84 wrote:

hopkinb wrote:

Scoob84 wrote:

My 4 grand canyon now sounds like i'm sharpening a knife even when just cruising along. Its driving me mad.

That's just a badly set up brake. As if you'd left a pad rubbing on the rim of a rim-braked bike and refused to do anything about it. Take the pads out, push the pistons all the way back into their housing, put the pads back in, loosen the caliper bolts, squeeze on the brake, tighten the caliper bolts. If that doesn't do it, then 5 mins aligning the caliper by eye will do it, and you'll be rub free until you change the wheel or have to replace the pads. Unless you have a bent rotor from a crash or something. Otherwise your 4 grand canyon is flexy like wet spaghetti, or your raw powaaah is causing a 4 grand bike to flex while cruising.

We can definitely rule out raw powaaah as a theory. Although i'm carrying some saggy bits, i'm under 80kg so we can probably rule my weight out of this.

I've tried lining us the brake as you describe a fair few times, to the point i'm now starting to round off the bolts. Admittedly i haven't tried poking the pads back in yet.

Annoyingly on the Canyon, the rub occurs at a certain point of the wheel revolution which suggests either a slight buckling or warping on the disc or maybe even a burr on the edge. But i can't see this by eye, and i can't imagine its damaged because its had an easy life since i bought it (new) and have barely ridden it to my shame. I've reached the point where i'll give it to a professional mechanic to fix.

But even on my genesis (mechanical discs and QR) i get a bit of rub when out of the saddle, but its fine when sat in it.

Sounds like you are onto it, if it's happening at a certain point then it suggests it's a warped rotor, just buy a new one or bend it back with an adjustable spanner (depending on the type or rotor, I have done this many times on mountain bikes, it's fine). My Genesis came with a slightly bent rotor due to delivery monkeys. With QRs you are likely to get a bit of rub out of the saddle, doesn't bother me too much as I'm usually at max hr and getting dropped...

zefs

Cheap 6 bolt rotors bend easily, try some Shimano center lock ones (if wheels accept center lock)

Livewire

Scoob84 wrote:

hopkinb wrote:

Scoob84 wrote:

My 4 grand canyon now sounds like i'm sharpening a knife even when just cruising along. Its driving me mad.

That's just a badly set up brake. As if you'd left a pad rubbing on the rim of a rim-braked bike and refused to do anything about it. Take the pads out, push the pistons all the way back into their housing, put the pads back in, loosen the caliper bolts, squeeze on the brake, tighten the caliper bolts. If that doesn't do it, then 5 mins aligning the caliper by eye will do it, and you'll be rub free until you change the wheel or have to replace the pads. Unless you have a bent rotor from a crash or something. Otherwise your 4 grand canyon is flexy like wet spaghetti, or your raw powaaah is causing a 4 grand bike to flex while cruising.

We can definitely rule out raw powaaah as a theory. Although i'm carrying some saggy bits, i'm under 80kg so we can probably rule my weight out of this.

I've tried lining us the brake as you describe a fair few times, to the point i'm now starting to round off the bolts. Admittedly i haven't tried poking the pads back in yet.

Annoyingly on the Canyon, the rub occurs at a certain point of the wheel revolution which suggests either a slight buckling or warping on the disc or maybe even a burr on the edge. But i can't see this by eye, and i can't imagine its damaged because its had an easy life since i bought it (new) and have barely ridden it to my shame. I've reached the point where i'll give it to a professional mechanic to fix.

But even on my genesis (mechanical discs and QR) i get a bit of rub when out of the saddle, but its fine when sat in it.

You need to push the pads/pistons back before realigning the caliper over the rotor. Spin the wheel with the bike upside down and watch the rotor spin in the caliper, it will be obvious if the rotor is bent.

And to reiterate what I said in a previous post;

Remove pads, push pistons back carefully, loosen caliper bolts, centre the calliper by eye over the disc, tighten bolts making sure the caliper is still centered over the disc, re fit pads, pump brake and away you go. Be sure the caliper does not move whilst you are tightening the bolts as calipers tend to move at the final point of tightening the bolts.

veronese68

Livewire wrote:

Be sure the caliper does not move whilst you are tightening the bolts as calipers tend to move at the final point of tightening the bolts.

Just to add to this, don't tighten one bolt all the way and then the other one. Tighten them up bit by bit, alternating from one to the other.

Scoob84

Appreciate the advice on this guys! Thanks you all, hopefully i can put this terrible issue behind me by the weekend and start loving disc brakes again!

Scoob84

Scoob84 wrote:

Appreciate the advice on this guys! Thanks you all, hopefully i can put this terrible issue behind me by the weekend and start loving disc brakes again!

I could kiss you all!!

It’s fixed. No more rubbing, I can’t believe it, such a relief!

veronese68

Excellent, pleased to hear it.