Do you have access to a wheel truing stand? If so, mount the wheel, then drill a hole in one side of the arms for the stand, then thread it and put a bolt in there that is long enough to reach in and touch the rotor.
Once you do this modification, you essentially can true wheels AND rotors. It’s not uncommon for us to get bikes brand new in the box with over-torqued bottom brackets, headsets, and bent rotors. Never hurts to double check the straightness. We have much better luck with longevity of Shimano disk components than SRAM - Hope and the like, well, we don’t recommend them for serious riders.
Is there any coloration to the rotors? The most common rotors are stamped sheet metal, and once they’re overheated they’re done for. If that’s the case, you can get some of the Shimano ICE rotors - they have aluminum for the core, and the best ones have a heat sink attached to the core that can get temps 150* below standard rotors. The forged aluminum spiders help with torsional stiffness too.
Nearly every rotor should be able to run with resin pads quietly. I know rubbing alcohol is the way to go per instructions, but the car guy in me grabs brake cleaner every time.
There is a chance that your caliper might be just a smidge offcenter - an easy way to check for this is to loosen the caliper bolts just enough for some movement, then apply the brake as hard as possible, and tighten the bolts while pressure is applied. This forces the caliper body and pads to be centered over the disk. We made a jig at the shop that we put over the rotor to ensure the pads hover a bit further away from the disk to reduced the chance of rubbing while riding, but you can replicate this with a business card on each side of the rotor, then clamping the brake lever down and tightening. Just make sure to open the pads up all the way before you begin if you try this with a tire lever so they start at the same distance from the rotor face, then insert the spacer, then loosen, then apply pressure (may take multiple pumps). Same concept.
It sounds like you ride hard. My suspicion is they have been overheated a smidge and lost some of the heat treatment, OR you have a caliper pot that isn’t fully retracting (happens a lot with the Deore calipers). I’d pull the wheel and work the pads back and forth with a tire lever and the brake lever, and be very observant if one is dragging slightly and not retracting with the same speed or distance as the other one. While the wheel is off I’d look very close at the rotors for discoloration. For reference - this is what a discolored rotor starts to look like (look at the tint at the rotorface vs the center
http://forums.mtbr.com/brake-time/ro...on-474549.html ). It will then go from that blue to a yellow then brown then purple with increasing amounts of excess heat.
Just remember that if you want more power, go to a bigger diameter. If you hit overheating, get aluminum-cored rotors. If this is better but not quite there, combine with ICE pads. If you still get overheating, go bigger and combine with the aluminum-cored components. The larger diameter will cool faster and offers more mass to distribute the heat evenly.
Originally Posted by cornstalker
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