Disc brake rub after cleaning every weekend

Hello all,

I’ve got a tiagra group set with disc brakes all round full hydraulics. Issue I’m getting is I take the front wheel off every weekend to clean it and when I put it back on the disc rubs? I don’t touch the lever, I take it out the work stand to make sure the wheel is in the dropouts straight. List of things I have tried below.

Re centre the calliper loosen the screws pull the lever and tighten.
Push the pads back in and pull the lever.
Been in to the shop and they said it need re centring so they did that, wheel off to clean back to rubbing again.

Going to the shop again isn’t an option with work hours and shop location.

Any ideas?

Is it quick release or through axle? With QRs, changes in how tight you pull it will flex the fork and move the rotor. Try and keep the tension more similar.

To be honest, if it’s only a slight rub, it might go away on its own when using the brake a couple of times.

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I have through axle. I have tried looking at the calliper when tightening the wheel back up and can see it move slightly but if anything it just pulls it straight in line where it should be.

The fork is probably also flexing, but with through axle, it should always end up in the same place, and the brake shouldn’t rub. Does pressing the brake lever a couple of times not help? My brakes always sounds like the rub after washing the bike, but it goes away as soon as I start riding.

Check that the caliper is aligned properly (sounds like you’ve done this) and the disc isn’t bent. Then take the bike for a quick spin and brake hard a few times. I’d guess the rub will go away.

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I usually don’t ride it straight after I have cleaned it I spin the wheel and can hear it straight away. Would you say taking it for a spin and braking a bit will help?

Yep. It’s not uncommon for my brakes to rub slightly after I clean my bikes. Not rubbing enough to stop the wheel quickly, but that annoying metallic ping every revolution. When the bike is dry, and after the first few brake pulls, the pinging goes away.

You can also take the pads out and then push the pistons back so there’s a bit more a of a gap as you would if fitting new pads.

It should help any odd centering issues. I’d have a look for the tool so you don’t score the pistons, about 15 quid from the good old ebay.

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I have tried this and it’s just goes back to scraping afterwards again. Can you centre the brake callipers on a work stand and get them to not rub?

You can just loosen the caliper, so it can move, and then clamp the lever tight, and while holding it tight, tighten the caliper bolts. That should centre it. But you shouldn’t need to do that after every wash!

And yes, to answer your other question - my rotors will sound like they rub when just spinning the wheel, but actually riding the bike and using the brake will make it go away quickly.

I have done the loosen and pull method and they still rub after that how can I centre them if that doesn’t work?

My disc brake bikes always rub when wet. So after cleaning, they’ll rub. It goes away when I ride. If I leave the bike wet, it sometimes rubs when I ride the next time, maybe because of rust or whatever residue. It doesn’t matter, as it goes away when I ride.

The rubbing when wet also happens when I ride in rain, especially through a puddle. When I say rub, I mean that it makes a sound. I very much doubt that it actually slows me down, even if it only lasts for a minute or so.

To conclude, I wouldn’t worry about it. And I definitively wouldn’t start adjusting the calipers.

I was having a similar issue with the SRAM brakes on my CX bike. I couldn’t figure out what it was, then stumbled across a suggestion to loosen the bleed screw on the brakes to see if there was any excess pressure. I loosened the screw, a little fluid pushed out, and that solved my problem.

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Update

Had the bike in the stand this morning trying to solve this issue. I took the pads out pushed the pistons back in then put the pads back in. Front wheel back in, loosened the caliper and tried the brake and hold method. No joy.

Wheel back out and pads out. Tried to clean the pistons round the edges and notices one is coming out before the other? I sprayed the caliper with a little disc cleaner and wiped it clean and still didn’t solve it. What can I do about the pistons? I’ve got them set up so you can hear a small scraping with your ear near the caliper. The rear doesn’t have this.

Watched this video today (haven’t tried it) but it might help solve your problem

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Dunno if shimano offers similar product, but Sram makes a grease for the calipers. I clean the pistons on my cx bike quite often. Alcohol and a q-tip to clean the dirty grease from a modestly extended piston. Apply grease with a q-tip. Repeat for the other side. Use a plastic tire lever or bleed block to work the pistons in and out a few times to work the grease in and verify smooth/even actuation. Clean any excess grease in the caliper housing with a paper towel and alcohol.

This video covers it all the clearest I’ve seen How To Clean Hydraulic Brake Pistons - Tech Tuesday #104 - YouTube