pulsing front brake

Discussion in 'Softail Models' started by gs34, Feb 1, 2009.

  1. gs34

    gs34 Junior Member

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    Soooo, Mama and I flew to Texas to spend a couple of weeks with my son and his family.
    And, as luck would have it, the weather has been excellent the last few days and being the good dad that I am, I have been exercising the sons FatBoy for him while he's at work.....Hey! that's OK, it needs the exercise and I'm glad to do it for him.
    However, I noticed right away that he is getting a pulsing when the front brake is applied. The harder you grab the brake, the heavier the pulse is.
    What do you think?....warped rotor? Or should I look somewhere else?
    Any thoughts?
     
  2. Mattman4403

    Mattman4403 Junior Member

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    Rotor is the simple answer. then you get into hung up pucks and several equally nasty things. better get it checked out.
     
  3. glider

    glider Veteran Member

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    More than likely a warped rotor, also check the steering head bearings.
     
  4. gs34

    gs34 Junior Member

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    Thanks guys. I'll take a look tomorrow. He doesn't have a dial indicator, but I might be able to see something if I get the wheel up and just rotate it using a stick taped to the fork leg as a fixed point of reference. If I don't see anything, I'll pull that front caliper and take a look there.
    I'll let you know what I find.
     
  5. glider

    glider Veteran Member

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    You'll see if it is warped by just rotating the wheel. It will get tight and loose as it turns as it contacts the pads.
     
  6. gs34

    gs34 Junior Member

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    Thanks Glider. I'll check it out and let you know.
     
  7. Bud White

    Bud White Well-Known Member Retired Moderators

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    I would agree warped rotor
     
  8. gs34

    gs34 Junior Member

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    Well, I finally got around to getting the front wheel off the ground so that I could rotate it freely, and it looks to me like it is warped.
    I taped a short piece of dowell rod to the front lower leg and used a feeler gauge between the end of the rod and the face of the rotor to get a rough measurememt. Looks to me to be between .035"-.040" out from the tight spot to the loosest spot.
    That makes for a total runout of at least .020".
    I would say that would be more than enough to cause a problem.
     
  9. glider

    glider Veteran Member

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    I agree there. Get a set of floating rotors if you are going to replace the rotor.
     
  10. gs34

    gs34 Junior Member

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    Yea, that would be the way I would choose to go. I'll make the recommendation to him and he can decide for himself. I don't even know at this point if he wants me to help him change it out or not. Most important lesson I was taught by Uncle Sam....don't volunteer for anything!!!