Re-surface brake rotors?

Discussion in 'GS Boxers' started by waddyp, Nov 12, 2012.

  1. waddyp

    waddyp Quite Content

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    At 50k miles on my '07 12GS, my front rotors are showing wear. Does anyone know: can they be 'turned' (re-surfaced)?
    #1
  2. 07wee

    07wee Adventurer

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    Its possible, but I've never been able to find a shop willing to do it around me.
    #2
  3. Idle

    Idle Been here awhile

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    I'm prolly gonna die.

    I resurfaced my front rotor while on the bike. I have a variable speed grinder and 4" diamond polishing pads.
    I only did the outside but plan on flipping it around to do the same to the inside in the next couple of days.

    I had a slight lip on the outside of my disc. I have since shimmed the caliper out so I felt I had to get the lip ground down to get 100% contact.

    Fwiw, I used a little water on the 300 grit diamond pad and it was a 310mm disc well in spec.
    #3
  4. def

    def Ginger th wonder dog

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    Resurface? No.

    But, what do you mean, "showing wear"?

    Rotors do show signs of friction from the pads.

    You'll need to determine rotor thickness and when out of spec, replace the rotors...kind of like tires.
    #4
  5. GS Addict

    GS Addict Pepperfool

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    Considering that the wear tolerance is .5 mm I don't see where the material is going to come from for a fresh surface on each side.
    These are not automobile rotors.
    #5
  6. Juvat

    Juvat Been here awhile

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    ^^^^ What he said.:deal If you try to shave those (and it is a shave) you could end up in a world of hurt. I'd just mic them to ensure the dimensions are still serviceable, through some new pads on and go!
    #6
  7. Juvat

    Juvat Been here awhile

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    Note: I did see somebody throw their disks on an auto lapping table and they came out pretty good. Not worth doing if you don't have ready access to one though, and it is total overkill. My buddy just did it for fun.
    #7
  8. Chat Lunatique

    Chat Lunatique aka El Gato Loco

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    Absolutely it can be done. As a tool & die maker I had lots of people bring me old bike and car parts to try and salvage them because SPARES WERE NOT AVAILABLE!

    One could set up the disc on an internal cylindrical grinder and remachine the faces with a cup wheel. Nice cross hatch pattern and good control over the amount of stock removal. Any other method can create disc wobble.

    Should it be done? Naw...too easy to warp them or go under the min thickness trying too clean them up. Best to pony up the cash for new ones.
    #8
  9. Disco Dean

    Disco Dean Long timer

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    Like he and he and he said... too thin to begin with and not worth the risk...

    There is a nice little Brembo logo on the disk that is stamped into the disk - if it has been worn clean/smooth the disk are done - at least in my measurements it has worked out perfectly that way.

    D.
    #9
  10. def

    def Ginger th wonder dog

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    :thumb

    If you insist on tinkering with motorcycle brake rotors, some sandpaper is allowed but, I would use caution....you're messing with the most important system on your motorcycle that may save your life one day.
    #10
  11. def

    def Ginger th wonder dog

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    Where? I've never seen it. Photo?
    #11
  12. Disco Dean

    Disco Dean Long timer

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    I'll post a photo later as I dropped off the wheel to get a new tire on and haven't picked it up yet. Damn Heidenau's are so friggin stiff... spoon those babies on...

    It is the Circular Brembo "b" logo and it sits half on the wear surface and half off on the inside of the disk. I have had other Brembo disks that have a similar placement.

    My bike is a 2006 R1200gs if it matters.

    I cannot confirm from Brembo that it is in fact a wear indicator - however it works to the specs perfectly - is situated to wear out with use and wears only half way to let you see that it is still there when the disks are worn out. As soon as I cannot make out the stamp - the disk mics out to the spec.

    If it is not - it is a coincidence that it works. Either way I mic the disk to be sure but it is a good visual indicator as to when I should check.
    #12
  13. def

    def Ginger th wonder dog

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    I have not observed it on my 2001 Brembo equipped GS. However, that doesn't mean that it is not there.
    #13
  14. lkchris

    lkchris Albuquerque

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    Taking the lip off is pretty funny. This is the place the pads never contact.
    #14
  15. ragtoplvr

    ragtoplvr Long timer

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    grooves are just more surface area.

    if not warped and you do not race, use it.

    Rod
    #15
  16. RTCHIEF

    RTCHIEF Been here awhile

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    New brake pads resurface the rotors to a degree. Has anyone ever tried making an abrasive pad that would take the place of the current rotor pad and resurface the disc when ever you used the brakes? Jon
    #16
  17. Rick Lee

    Rick Lee Long timer

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    That's true, but it makes visual inspections a lot easier. I just feel the lip on car rotors. If you can take it down to even with the rest of the surface, it's a lot easier to watch for a lip to develop than to mic it out.
    #17
  18. dualsportride

    dualsportride Been here awhile

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    I wouldn't chance it unless you just can't find a rotor for your bike. I would try to save a few bucks somewhere else breaking is just to important on any object in motion.
    #18
  19. SloDon

    SloDon Hey...where am I?

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    Me thinks you have way too much time on your hands..........apparently I do to.........


    Sent from my iPad using Tapatalk HD
    #19
  20. def

    def Ginger th wonder dog

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    Yes it is.
    #20