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    Two new brake rotors are also wobbling. What could be the problem?


    Hi everyone,

    My brake rotor is wobbling, as you can see in the video. So I bought a brand-new one, but it wobbles just like the old one.

    I took the wheel to a shop for truing, but that didn’t fix the rotor wobble.
    Both rotors wobble the same way and in the same spot, so the issue isn’t with them.

    Its a Crankbrothers rim.

    Any ideas? Could the hub be the problem?

    Thanks for your help!

    Two new brake rotors are also wobbling. What could be the problem?
    byu/Any-Drive3685 inbikewrench



    by Any-Drive3685

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    33 Comments

    1. walton_jonez on

      The rim isn’t an issue when a rotor wobbles. It’s either the rotor or the hub. Some new rotors come bent because accidents happen. Lay it on a flat surface and see if it’s straight.

    3. Switchen on

      > I took the wheel to a shop for truing, but that didn’t fix the rotor wobble.

      Yup. Trueing a wheel doesn’t affect disc brakes in any way. 

      When you say the rotors wobble in the same spot, what is “the same spot” relative to? If you take a rotor and rotate it 180 degrees relative to the hub, does the wobble follow the hub or the rotor?

    4. DeadBy2050 on

      Sounds like it’s a hub issue. So replace that.

      Altneratively, true the rotor. It might work well enough.

    5. Melodic_Theme7364 on

      Just true the rotor with your hands but make sure you’re wearing gloves or with an adjustable wrench. It’s not uncommon for new rotors to be bent slightly from shipping. If you’re not comfortable doing it yourself just bring it to a shop.

    6. Reasonable_Loquat874 on

      I’d probably just bend the rotor a bit where it’s rubbing and not start messing with the hub unless there are other issues. Park Tools makes a tool for this.

    9. K9ChewToy on

      Looks like the whole wheel/tire is moving at the same time as the rotor bend. That’s a strange one.

    10. Working-Promotion728 on

      I would never expect a brand new rotor to be perfectly 100% straight. You need to bolt it to the hub and then fine tune it to make sure everything is perfect after the installation.

    12. nhluhr on

      Just like a brand new derailleur hanger, when you install it, it will always require some amount of straightening.

      There’s a tool for it.

    13. TheWorstePirate on

      Can you post a video that isn’t so zoomed in on the rotor? In this video it looks like your entire hub is violently shaking. Show the hub from the side.

    14. Either-Reference9768 on

      its not straight so straighten it or take it to a bikeshop and if they know what they are doing they will straighten it

    15. terdward on

      If does not wobble when it is flat on a flat surface then something with your hub is not true. Easiest thing to do is the equivalent on an on-car tire balance. You’ll bend the rotor slightly to compensate for the hub wobble. But this is only a bandaid. The real fix is to figure out what’s up with your hub. It sounds like it needs servicing.

    16. berniefist on

      What kind of axle is it? I’ve had a similar problem after putting a good size dent in a QR axle. The whole wheel can be true, but wobbles on an elliptical axis.

    17. Toulo on

      It’s just a wobble. Just live with it. If it’s not rubbing don’t worry too much about, it’ll stop you fine. Just ride.

    20. Fun-Description-9985 on

      Have yet to have a brand new rotor that’s straight. They *always* need truing, to some extent or another. This is normal.

      Did you tell the bike shop the issue was with the rotor? Or just ask them to true the wheel? Truing a rotor takes about 5mins, tops.

    21. Stunrise on

      I just had exactly the same with my eBike – Brake Rotors were wabbling so I bought a new one and it was wabbling the same way again.

      I had to replace the front wheel, because the hub with the Centerlock mount was bent and it was cheaper just to buy a new front wheel online then to just replace the hub of the old wheel.

      With the new front wheel everything is perfectly fine, it was about 50€ total.

    23. Regular-Host-7738 on

      Just straight it! What a problem?
      Just take adjustable wrench and do it! It will take 3-5 minutes.

    24. Mis-Fit on

      Your hub is wobbling all over, the rotor is just magnifying it. Small runout at the hub will be amplified inches out at the rotor edge.

    25. MariachiArchery on

      Yeah… you might have something wrong with your hub. It could be the case that the brake rotor mount face on the hub just isn’t flat, which isn’t something you can fix without finding a machine shop who would be willing to do the work. And, that isn’t a tree you should bark up. You could also have your shop do a hub overhaul. That is about all you can do here without really thinking outside of the box.

      Honestly man, just bend the rotor. Don’t use a tool, like other are suggesting, you don’t need that, and you will probably end up fucking the rotor up.

      Just use your thumbs. It looks like you’ve got an outboard wobble here, so, spin the wheel slowly, find the high spot, and just push the rotor with your thumbs. Bend it by hand. Then, look, listen, and repeat.

      That is what I would do here, and that is what we do in the shop. We do it all the time and we never use tools, because the odds of you kinking the rotor or overcorrecting it are too high. Just use your hands.

      Also, you should where some gloves for this. We wear nitrile in the shop. Otherwise, you’ll contaminate the rotor/pads.

    26. lune19 on

      Looks like everything is wobbling. May be adjust your wheel centered and check again.

    28. Expert_Document5401 on

      I see that coming on new bikes, all the time and new rotors out of the box

    33. redditusername_17 on

      Take the wheel out, check the wheel and drop outs for dirt and debris. It could be preventing your wheel from going in straight.

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