SQ: I’ve got a hydro disc caliper that’s rubbing pretty loud. Doesn’t feel draggy but it’s very annoying. I tried resetting it, but if anything that made it worse. The weird thing is that if I pull on the lever just a little bit, like not even enough to get the pads to really bite, the rubbing noise goes away. I have no idea what’s going on except maybe that the pads are worn in some weird uneven way. Anybody have a better idea?
Is your caliper loose? Is it centered? Try undoing the bolts until it can wiggle, squeezing, and then tightening the bolts with care taken not to push the caliper this way or that with the torque of tightening.
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I did that 2 or 3 times already. Not going to say I did it right! But I did try it! And actually I did do it to the rear caliper on that bike and it was perfectly silent so maybe I did do it right!
You prolly did it right. Have you like pressed the lever while looking at the caliper pads? You should be able to see what’s going on.
take pads out and reset the pistons, then put pads back in and retry centering the caliper?
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It’s probably time to clean your pistons.
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I think this is probably it. I did depress the pistons at one point but I have a feeling they aren’t retracting enough or they retracting weird. And as the video says, I probably “fed my seals some junk”
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I had that exact same issue twice on one bike. First time it took a few goes at aligning the caliper and truing the rotor to get it to go away. It was a new bike so I figured that was just initial assembly misalignment. Then a few weeks later it magically came back on a ride home from work one day and got quite a bit worse just in those 3-4 miles. That second time, a small pull on the lever would make it go away. Both times, right turns made it better, left turns made it much worse. The day before that second time I had removed and reinstalled the front wheel, but didn’t mess with the brakes at all.
So far my working theory is that the order I had been tightening the nuts on the front wheel was causing the misalignment to happen because I did notice a difference between snugging up one side first vs the other. The hub bearings didn’t/don’t feel loose. A similar thing happens on another bike with a QR front wheel. Sometimes I have to release the QR, rock the wheel side to side, and tighten the QA a few times, or even mess with the caliper alignment anytime to front wheel has to come off. Now, both have to be checked for rotor rub anytime a wheel comes off, annoying.
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That does sound very similar to the problem I’m having, but since the brakes are so scuzzy, I am going to give the q-tips and mineral oil a try.
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I’ve got an IS tab on my NFE thru axle fork. I’d been running a 180mm rotor for past years but was getting some shudder under harder braking, even after I cleaned the pads and rotor. So when pads were done, I moved to 160mm rotor. The 160 adaptor meant the Shimano caliper hit the IS tab as there was quite a bit of material around the upper bolt hole. Me and my Dremel removed enough material from outside of tab (about 2mm) to allow caliper to move outboard so rotor can now fit. There’s still several mm of material around the caliper bolt washers after the dremel.
Am I going straight to hell? I tried Avid and Shimano adaptors and had same interference issue. Glen designs these bikes around 160mm rotors, so it’s a bit of a head scratcher that I had to do this.
Curious if this something you folks have done before and if I should be watching the IS tabs for cracks etc?
If i had any leggo i would try this technique.
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I was so frustrated with a wobbley rotor i brougnt a new one. It did exactly the same thing, wobble. Does that mean my rotor mount surfaces need facing?
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same thing happened to me!
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Just bend them straight? Are they going out of true while JRA or are they wobbly out the box?
I’ve had the second but never the first.
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Rudy’s solution should work whether the rotor is bent or the mounting surface is off perpendicular from the axis of rotation.
If there is a problem with play in the bearings that could possibly also cause some lateral or off axis play maybe. I’d expect it to be intermittent or variable in this case.
They are not wobbly until mounted. Hence the question, can the mount faces be off? Brand new rotor.
Yeah, it seems consistent. You can see it, not just feel it. Tried truing but i guess im not that good at it ; ) pretty sure bearings are good. Can recheck tho. Hadnt thought of that.
Note where it’s out, clock it differently and compare?
I’d say a good 20% of new rotors end up befitting from some truing once mounted. So there’s that.
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What’s the seatpost collar to buy? Salsa?
The wolf toots one on my MTB is slip slip slippy.
Did ya try carbon assembly paste on the post and grease on the hardware? What size post? Try another?