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  • Pulsing front brake

    The XJ650 had a minor lay-down incident. My son,who is still learning misjudged a low speed corner. He ended up in someone's front yard in the soft grass. We had to replace some divits and he was not hurt except for the pride thing. The crash bars did their job but the impact was enough to bend the handle bar and the crash bars a little. Nothing that could not be cold straightened. While test riding after the repairs I noticed a pulse when the front brake was applied. Started checking stuff and ended up replacing the bearings and seals in the front end. The disk looks true when you spin it and the pads in the brake are new. Also replaced the fork seals as one was seeping even before the crash. Any ideas where this pulse is coming from?
    wingnut
    81 SH (Daily Ride)
    81 650XJ (Brother in laws bike, Delivered)
    81 650XJ Jane Doe (Son's Ride)
    82 750XJ Project bike (Son in law's future ride)
    81 XS 400

    No man has a natural right to commit aggression on the equal rights of another; and this is all from which the laws ought to restrain him.”

    A government big enough to give you everything you want, is strong enough to take everything you have.

    Thomas Jefferson

  • #2
    neither of my disks look warped or bent ...they both are . i've replaced one of them and the pulsating is down by 80% . supprisingly it doesn't take much to bend or warp them , which you'd never assume by looking at those huge slabs of rotor .

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    • #3
      I got to play in the garage a little today after all the holiday stuff. I put a dial indicator on the side of the disk and it is wrapped. The book spec calls out .006 TIR max and this one is at .010. Took the indicator over to the XS just for a reference and its run-out was about .001. Kind of worried about just buying one off of EBay. One of those could be worse.... Any one every had any success with tiring to straighten one using a press?
      Last edited by wingnut; 01-01-2010, 05:22 PM.
      wingnut
      81 SH (Daily Ride)
      81 650XJ (Brother in laws bike, Delivered)
      81 650XJ Jane Doe (Son's Ride)
      82 750XJ Project bike (Son in law's future ride)
      81 XS 400

      No man has a natural right to commit aggression on the equal rights of another; and this is all from which the laws ought to restrain him.”

      A government big enough to give you everything you want, is strong enough to take everything you have.

      Thomas Jefferson

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      • #4
        If you can't find a shop that can surface grind the old ones flat, then the only option is to replace them.

        The good news is warped rotors is a rare problem. Also the minimum rated thickness is very generous. You could take them down to 5.5mm thick and not have any problems.

        Geezer
        Hi my name is Tony and I'm a bikeoholic.

        The old gray biker ain't what he used to be.

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        • #5
          Someone on here was supposed to get some imported floating rotors in for the 11's.. Geezer, was that you?


          Tod
          Try your hardest to be the kind of person your dog thinks you are.

          You can live to be 100, as long as you give up everything that would make you want to live to be 100!

          Current bikes:
          '06 Suzuki DR650
          *'82 XJ1100 with the 1179 kit. "Mad Maxim"
          '82 XJ1100 Completely stock fixer-upper
          '82 XJ1100 Bagger fixer-upper
          '82 XJ1100 Motor/frame and lots of boxes of parts
          '82 XJ1100 Parts bike
          '81 XS1100 Special
          '81 YZ250
          '80 XS850 Special
          '80 XR100
          *Crashed/Totalled, still own

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          • #6
            Originally posted by trbig View Post
            Someone on here was supposed to get some imported floating rotors in for the 11's.. Geezer, was that you?
            Tod
            Yes that was me but I've hit a couple of problems and the project is going to be delayed or scrapped. I'd like to get these too especially since they will be about half the weight of stock rotors.

            Tony
            Hi my name is Tony and I'm a bikeoholic.

            The old gray biker ain't what he used to be.

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            • #7
              Originally posted by Geezer View Post
              I'd like to get these too especially since they will be about half the weight of stock rotors.
              Just go to the bathroom before you ride and the weight difference will be the same.
              http://www.myspace.com/i_give_you_power

              1980 XS11 Special - chopped, dropped and OCTY is still installed - NOW IT'S FOR SALE! $1,800 OBO


              Famous Myspace quote:

              "Don't mess with TEXAS! It's not nice to pick on retards."

              It's funny because I am from TEXAS!

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              • #8
                Originally posted by Montreux_Blue View Post
                Just go to the bathroom before you ride and the weight difference will be the same.
                We are talking unsprung weight here...

                Geezer
                Hi my name is Tony and I'm a bikeoholic.

                The old gray biker ain't what he used to be.

                Comment


                • #9
                  Fix for warped brake rotors

                  If you search in e bay for xs1100 brake rotors, you will find a company from Portland OR that does surface grinding for $49.99. It claims their process corrects warpage. You might want to contact them with the measurements you mention to see if they can correct that much.
                  I just sent my rear rotor to be surfaced and drilled as they do both things for $95.00.
                  Good luck.
                  Last edited by Tropic-al; 01-03-2010, 09:26 PM.
                  79 XS1100F.
                  SuperTrapp 4-1 w/center stand.
                  TC's fuse box.
                  SOFA filter.
                  Venture cam chain adjuster.
                  Tkat fork brace.
                  Progressive fork springs.

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