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I'm building up a 2014 specialized awol frame with fulcrum red power wheels and trp hylex brakes. I'm using the rotors that came included with the trp's. My issue is that there does not seem to be enough clearance between the pads. The rotor is constantly rubbing. I've removed the pads and reset the pistons. I've used the self centring technique (mounting the wheel then squeezing the lever before fully tightening calliper mounting bolts). All to no avail. It doesn't make sense that I don't have the clearance as I'm using the packaged rotor. Any suggestions?

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  • Have you bedded in the brakes yet? A bit of rubbing should sort itself out as you do the ~30 hard stops required to bed in the brakes fully. – Criggie May 3 '17 at 4:33
  • Any chance the QR has moved a bit since you set the caliper? I found the front wheel didn't always settle well into the awol fork. – Rider_X May 6 '17 at 1:01
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Many brakes just don't work very well with the squeeze-the-lever-and-tighten-the-bolts technique, despite whatever the manufacturer says. It's worth trying but also something that needs to be given up on quickly if it doesn't just work.

Centering it by eye using a white paper as backdrop is a normal thing to have to do. Don't overtighten the caliper bolts; 8nm is all you need and will generally let you avoid squirm.

While you have the white paper out, make sure to check out your parallelism, and get the mounts faced if needed.

You don't indicate how true the rotors are. Many need truing out of the box - again it's not necessarily how it's supposed to be, but it's how it is.

Unlike what's sometimes seen with DOT brakes, brand new mineral oil brakes such as this usually don't actually have issues with the pistons being overextended and not able to retract fully. You can double check that you're good on that front by taking the pads out and confirming that you're able to push the piston faces down level with where the pad will sit against the caliper body. If you can't, that's weird, but it would mean you'd need to either bleed the brake or potentially burp some fluid and then bleed if it doesn't go smoothly enough.

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