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  1. #1
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    juicy 7 rear bleed

    There was a more than tolerable amount of play in my rear brake lever and I would really need to crank down on the lever to get the rear brakes to stop the tire. All research pointed to getting a brake bleed so I took it upon myself to buy an Avid bleed kit and bleed them myself. However, now that I've bled them, the issue is actually worse. I now have 2 problems:

    1. ) There is resistance on the rotor even when the brake lever isn't compressed so that the rear tire does not spin freely. It seems like the brake pads are not properly aligned with the rotor. A little bit of googling suggests that I may need to readjust the calipers. Anyone familiar with this procedure?
    2. ) I need to compress the brake lever down all the way to the handlegrip to get the pads to properly engage the rotor. So I made the initial problem worse.

    I'm sure that it was something I did incorrectly, but I followed the instructions to a tee and even consulted a few online videos (including SRAMs) on how to properly bleed the brakes. I will probably end up taking it to my LBS to have them fix my mess, but I'd really like to know what I did wrong so that in the future I can do the maintenance myself.

    One part of the procedure that I'm still not 100% on, is the compression of the brake lever while pushing the fluid from the caliper to the reservoir. According to the Avid manual that came with the kit, it's suggested not to compress the brake lever, but the sram videos show them tying the brake lever fully compressed to the handlegrip with a toe strap. I followed the procedure in the video, and I'm wondering if this was part (or all) of my problem.

    I'm going to try performing the bleed again tonight when I get home from work. If anyone has any suggestions (aside from take it to the LBS ) it would be greatly appreciated.

  2. #2
    Never enough time to ride
    Reputation: squish's Avatar
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    If your pads are touching the rotors now with out being compressed it's likely that you inadvertently pushed the pistons out while you were doing the bleed. It happens, all you need to do is take a 9 or 10mm box end wrench and push the pistons back into their bores. Sometimes having the bleed screw on the master cylinder open when you do this is helpful so excess fluid can escape.

    Centering is very easy, you loosen the two caliper mounting bolts (not the adapter bolts) squeeze the lever a few times then hold it while tightening the bolts back down. Best done with a torque wrench if you have one. 80 in/lbs is all they're looking for.

    When bleeding there are two things to look out for, make sure that your pad contact adjuster is turned all the way out, or you won't get a proper bleed. And when your bleeding the caliper you do need to pull the lever all the way to the bar, but make sure at least one of your bleed ports is open and you have a syringe attached and open, or you'll push the pistons out. Take your time, you may have to do it a couple of times on your first attempt before you get the feel for it.

    Hope this helps a bit.

    happy trails...

    squish
    Get out and ride!

  3. #3
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    Thanks Squish,
    That definitely helps. I'm the kind of person that needs to hear the same thing 10 different ways before I fully understand it. It's possible that I might have have the brake lever pulled to the bar during the wrong step.

    A question about the pistons being pushed out during the bleed... If I have a bleed block in the caliper while I was doing the bleed. That should keep the pistons from moving correct?
    Along the same lines, In order to get the bleed block into the caliper, I removed the bottom caliper mounting bolt to swivel the caliper out so I had room to insert the bleed block. I re-attached the caliper to the mount before I did the bleed, but I certainly didn't tighten it (knowing that I would have to disconnect it when I was done to remove the bleed block). Could unmounting and remounting that caliper (both before and after the bleed) screw up the process?

    Thanks again for your help

  4. #4
    Never enough time to ride
    Reputation: squish's Avatar
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    Removing your caliper bolt won't screw with your bleed at all, but it will kill your caliper alignment! That's probably where your rotor rub is coming from now, just use what I have in my first post to realign your caliper and you should be golden. Also make sure you have your spacers back in, in the correct order. And if your using a bleed block there's not much worry of your pistons popping out.

    happy trails...

    squish
    Get out and ride!

  5. #5
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    If you want to take your caliper apart and check out the pistons, there is step by step instructions with pictures on SRAMs website. Go to the Avid section and download the bike shop technical manual. It will explain the whole process. It's very easy to do, but sadly you'll need to re-bleed because of the disconnecting.

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