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Brake Deglazing?

Discussion in 'Downhill & Freeride' started by Inclag, May 11, 2019.

  1. Inclag

    Inclag Turbo Monkey

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    Pretty simple really. Anyone have any good methods to deglaze a brake? Pretty frustrating when a pad and rotor have 95% life but take 20 ft to stop you when just rolling along on flat pavement.
     

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  2. johnbryanpeters

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    If it's glazing, sandpaper. If it's contamination with oil, grease, or brake fluid, toss the pads.
     
  3. Jm_

    Jm_ Turbo Monkey

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    For contamination, remove pads, clean with alcohol, bake at 400F for 15-20 minutes (be sure to wipe down the rotors too with alcohol). This has a 100% success rate for me, which is something I struggled with for years (contaminated pads and how to clean without giving up).
     
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  4. Udi

    Udi RM Chief Ornithologist: “I Brake for Birds”

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    I've discussed this before in the brake thread, if you're riding DH (and/or are a heavier rider), this is what sintered pads do. You can try sandpaper but the heat damage (it's a heat hardening/aging rather than just surface glazing in my experience) usually goes right through the sintered material.

    The long-term solutions are to either switch to non-sintered pads, or if sintered pads are absolutely necessary, make sure they are the Shimano heatsink ones. No other brand heatsink pad is constructed correctly in my experience. They will still deteriorate with heat exposure but at a slower rate.

    However, on johnbryanpeters' note, if you're running Shimano brakes it's also common for them (especially when left unridden for some time) to weep oil onto the pads, in which case the solution is the same as above - replace the pads.

    Finally, there's another separate problem that happens with older rotors - the braking track wears faster in the center (where ventilated) leaving a concave profile. When new pads are installed, it takes some time for them to match the concave rotor profile - which results in (particularly, and IME only in the case of sintered metal pads) a portion of the pad surface being exposed to higher localised temperatures, which results in glazing (or permanent heat damage to the pad) occurring much faster than if the surfaces were mated in less time. Obviously this is logically a far bigger problem with sintered metal pads because the slower wear rate means far more braking is done before the pad reaches full surface contact.
     
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  5. Westy

    Westy the teste

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    Under medium heat add wine or stock. Stir while reducing.
     
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  6. johnbryanpeters

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    Finish with tender application of angle grinder.
     
  7. englertracing

    englertracing Monkey

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    Pea on them...
    learn how over on facial abuse dot com
    jk....

    if contaminated put them in the trash or throw them into your neighbors front yard
    if the rotors are concave throw it like Zena the princess warrior, preferably at the dude who designed the vents because he sucks ballz or you your using a pad that is not the correct height for the rotor, they are supposed to be designed with the holes evenly distributed across the rotor so they wear evenly.
    B12 carburetor cleaner
    pull the pads off spray em down, lap them wet with 280 to 320 grit sand paper on a granite stone or plate glass, wash them with water after that.
    for the rotor maroon scotch bright with b12 fer dayz. then clean it up more with ragz n moar b12.

    re bed..... with a big ass paved hill and bursts of braking with cooling between.

    then visit facial abuse
     
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  8. Katz

    Katz Monkey

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    I've used a blow torch in the past (with success, I might add) when I was in hurry, but that sounds like a more sensible approach.

    My ultimate solution was to ditch Shimano brakes entirely, so I don't have to bleed the damned brakes before every ride.
     
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  9. Jm_

    Jm_ Turbo Monkey

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    Well, the other solution is to ride all of your bikes every day and not let them sit for 2 weeks. Gets kind of hard to do after a while though.
     
  10. jonKranked

    jonKranked Press Button, Receive Stupid

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    In a pinch I've rubbed brake pads against a very flat rock mid ride when this has happened. It works well enough to not die the remainder of the ride, then attend to a proper fix post ride.
     
  11. Jm_

    Jm_ Turbo Monkey

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    Avid mechs used to glaze over bad for me on big descents. Braking and deathgrip were inversely proportional.
     
  12. Westy

    Westy the teste

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    Smearing mud on the rotors can also help in a pinch, just find proper mineral mud and not the loamy organic stuff.
     
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  13. TrumbullHucker

    TrumbullHucker trumbullruxer

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    Bake em while you visit the shed
     
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  14. maxyedor

    maxyedor <b>TOOL PRO</b>

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    I sand the pads lightly on a flat surface, then soak in alcohol, heat up with a torch or in the toaster over, lightly sand the rotor and put it all back together. Seems to work.

    QUOTE="Katz, post: 4344787, member: 71870"]I've used a blow torch in the past (with success, I might add) when I was in hurry, but that sounds like a more sensible approach.

    My ultimate solution was to ditch Shimano brakes entirely, so I don't have to bleed the damned brakes before every ride.[/QUOTE]

    The torch is generally my go to as well, but you gotta be careful, I exploded all the sintered material off my Magura pads once. Hot flying brake pad material is uncomfortable when it hits your arm.
     
  15. jeremy_2640

    jeremy_2640 Chimp

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    I use one of these every now and again -

    Very little effort and with a new consumable it doesn't contaminate the rotor.

    Plus they look new after it..
     
  16. Sandwich

    Sandwich Pig my fish!
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    I remember when you poured Dr Pepper on your Codes to get them to suck less
     
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  17. 6thElement

    6thElement Schrodinger's Immigrant

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    The only way to make original Codes suck less was to sell them.
     
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  18. sundaydoug

    sundaydoug Monkey

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    As a long-time Shimano brake user (Udi's mention of fluid seepage onto pads after long periods of non-use) I've done the following once or twice per season with success:

    Remove rotors and pads
    Spray light application of brake cleaner to rotors and pads
    Clean all thoroughly with a clean paper towel
    Lightly sand surfaces of pads and rotors
    Repeat brake cleaner application and clean w/paper towel
    Reinstall
    Finish with proper bed-in procedure
    Go ride
     
  19. mdc

    mdc Monkey

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    Rubbing alcohol and a Scotch Bright pad for the rotors. Sanding and a butane torch for the pads. Or just buy new pads and avoid a big hassle....
     
  20. Bike078

    Bike078 Monkey

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    Same here. Sand paper and alcohol on rotors and pads. Hold the pads over a gas stove flame if contaminated, clean again with alcohol then re-install.