Rear Brake keeps Dragging

Discussion in 'Wheels' started by tallbill17, Nov 28, 2012.

  1. tallbill17

    tallbill17 New Member

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    Hi, I have a 87 FLHTC 50k miles, my rear caliper started dragging to the point it was slowing down my speed. But it would seem to do this after going for about 5 miles,even on interstate where I would not be using the brake at all. So I cleaned the caliper good but still had the same problem, So I got a rebuild kit and new pads from HD (with new pistton) and did that. Still have the same problem. That narrows down Master Cyc. or Brake lines. My question is what which should I do first?
     
  2. Breeze3at

    Breeze3at Well-Known Member

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    The master cylinder valve assembly has a relief or bypass orifice that relieves pressure when the brake is released. As old as your bike is, it's likely that it is clogged and causing your brake to drag. A rebuild kit is not expensive and easy to install. It's a good idea to flush entire system with new fluid of the correct DOT#.
     
  3. HDDon

    HDDon Experienced Member Contributor Retired Moderators

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    Have you checked the runout on the brake disc? Buddy had one that the disc was warped and would heat up the caliper and cause the fluid to get so hot that the pads would seize and stop the bike.
     
  4. Jack Klarich

    Jack Klarich Expert Member

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    Agree with Breeze, you can con firm the master bad by cracking the bleeder when the brake locks up, if you have residual pressure fluid should squirt out, master cylinder replacement with total flush of correct fluid and check free travel of push rod:s
     
  5. fin_676

    fin_676 Experienced Member Staff Member Moderator Contributor

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    I had a wee bit of brake drag from time to time earlier this year then there was no brake a master cylinder rebuild kit did the trick

    Brian
     
  6. tallbill17

    tallbill17 New Member

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    Ok thanks I guess I will rebuilt the Master next.. and flush out all the lines also,