Front brake disc on R100GS is bent. Looking for options...

Discussion in 'Airheads' started by Mane, Dec 9, 2011.

  1. Mane

    Mane Been here awhile

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    566
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    Hi,

    It turns out that my front brake disc is bent and the OEM replacement is $470.00 at MAX BMW. I've decided to look up for alternatives on aftermarket and might even consider this as an opportunity to upgrade the well know weak front brake performance on airheads (if it does not get too spendy...)

    Someone at this site recommend me to look at EBC rotors and I've been having trouble to find an online source with a working website to find parts and prices. Does anybody knows the EBC part number for a R100GS brake rotor?

    What about another vendor? is the EBC the best or only option for our old airhead GS?

    If there a kit for improve braking performer I should look up instead (Garrison o Garrent, don't remember)?

    Thanks for you help!

    Regards
    Mane
    #1
  2. One Less Harley

    One Less Harley OH.THAT'S GONNA HURT

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    Ted Porter EBC $219.00, the rotor carrier is bare AL I painted mine black.

    [​IMG]

    [​IMG]
    #2
  3. disston

    disston ShadeTreeExpert

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    I think you have Brembo brakes on that bike. It's the earlier ones with Ates that cause all the grief. Although your Brembos will also see some improvement with the semi-floating EBC rotors.

    Charlie
    #3
  4. Crisis management

    Crisis management Latte riders FTW!

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    Motobins or Motorworks out of England?

    How bent is it, I have straightened a few discs with a copper faced hammer and a something solid to rest it on, sometimes successfully, sometimes not.... :D But, if it's bent now, how can you make it any worse?

    Find the high or low points on the disc and mark with something (permanent marker?) remove from wheel, rest over an open vice and hit the high point with a sharp and decisive blow, tapping won't do it. Repeat until straight.

    Seriously, this can work and a couple of hours work may save you some serious $.
    #4
  5. Rob Farmer

    Rob Farmer Long timer

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    Motobins will tell you they don't do an EBC replacement for the 100GS but you can get a floating EBC that fits straight in. Drop Arkwright2007 a line. He bought one for his bike.
    #5
  6. Mane

    Mane Been here awhile

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    Hey, thanks for the heads up!

    Regards,
    Mane
    #6
  7. Mane

    Mane Been here awhile

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    Charlie,

    Could you please explain these a little bit more? Are you saying that early airhead GS (and G/S for that matter...) didn't always came with brembo brakes?

    regards,
    Mane
    #7
  8. Solo Lobo

    Solo Lobo airhead or nothing

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    All the GS's and G/S's came with Brembo's

    The German HE 320mm rotor that comes with the caliper spacer are really great, much better than stock
    #8
  9. Mane

    Mane Been here awhile

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    Solo,

    Thank you for the confirmation,

    Is there a local source for these German HE 320mm rotor and caliper spacer in the US?

    Do you have any pics to share?

    regards,
    Mane
    #9
  10. disston

    disston ShadeTreeExpert

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    I didn't know that any Brembo's had problems. The comment that the OP made about "upgrade the well know weak front brake performance on airheads" made me think of Ates.

    You're right I know nothing about GS or G/S.

    Charlie
    #10
  11. One Less Harley

    One Less Harley OH.THAT'S GONNA HURT

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    The G/S and GS have Brembos, not the 4 pot I have pictured though. The four pot is easy to get and put on. Conversion
    #11
  12. Beemerboff

    Beemerboff Long timer

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    Wemoto do a Kyoto OEM quality disk for the GS at a sensible price and they work well.

    My GS had a 48 mm twin piston caliper which worked well enough, but if you must change make certain that you get one that you can get HH rated pads for - the PO of my G/S had gone down the four piston large disk route but it wasnt until I added EBC HH102 pads that it was any better than stock.

    The correct M/C is essential - aim for a ratio of between 25 to 30 to one between the slave and the master cylinder if at all possible - Motorworks have 12 mm MC s to fit almost everything at a sensible price and they are the best bang for the buck you will get - and if you can bleed brakes any extra lever travel will be unnoticable.
    #12
  13. Blady Hassel

    Blady Hassel Hasselblady

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    Hi,
    i just got my Ferodo rotor as a replacement for my '93 R80GS original one. Mine is bent. I'm just not sure what the rignt way of installing is (there's no instruction inside), but seems to be easy.
    the one i bought is:
    [​IMG]
    .
    [​IMG]
    .
    [​IMG]
    .
    [​IMG]
    .
    with the old one
    [​IMG]
    .
    and finally should look like that
    [​IMG]
    .
    these are the mounting pieces
    [​IMG]
    .
    [​IMG]
    the curvy one is round shaped though it looks different from this angle

    I'm just not 100% sure if that's the right way of mounting is but seems to be no other way to me (but never done that before and i'm a real newbe in mechanics:)

    The rotor is a replacement for different models so i guess they give two screws to choose the right one. I think it should go like that .Please correct me if i'm wrong.
    [​IMG]
    .
    where the rotor disc is here
    [​IMG]

    so mounting should look like that
    [​IMG]
    .
    [​IMG]

    and that cushioning (?) washer should probably be placed this way
    [​IMG]

    not like the second photo i guess :)
    [​IMG]

    Has anyone done that before. Am i right? Please correct me :)
    #13
  14. darklight79

    darklight79 drink it , ride it , nail it

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    Nice find what did the disk cost ? I wasnt aware that the disc would separate from stock carrier . Is you stock carrier staight ? Your bolt config looks right nice find where did you find this unit?
    #14
  15. Blady Hassel

    Blady Hassel Hasselblady

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    #15
  16. Kai Ju

    Kai Ju Long timer

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    The sequence should be:

    Bolt - spacer - rotor - wavewasher - carrier - flatwasher - nut.

    At least that's my best guess, which will also make the rotor a semi floating rotor.
    The spacer should bottom out against the carrier with the rotor loose on the spacer except for the wavewasher keeping it from rattling around. The flat washer provides a steel surface for the nut to bear against.
    #16
  17. Blady Hassel

    Blady Hassel Hasselblady

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    But rotor is on the carrier originaly. Placing anything between is going to change the distance and wouldn't fit or wouldn't fit correctly in brake caliper. The other thing is that it's going to be loose (i guess they would give a different shaped wavewasher if it was supposed to be between rotor and carrier), i guess the only place it fits just right (by size and shape) is the way i did it on the photo.
    #17
  18. Kai Ju

    Kai Ju Long timer

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    what screwed me up is that the carrier wasn't listed in your sequence.
    I concur with you, bolt - spacer - wavewasher - rotor - carrier - flat washer - nut.

    Sorry 'bout that.
    #18
  19. Rapid Dog

    Rapid Dog bikes, booze, broads...

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    bump!
    #19
  20. Stashek

    Stashek Adventurer

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    Hi there
    The way you have it in the photos is the same way as I fitted mine and its been on there for a couple of years with no problems. I replaced my OEM Brembo two pot caliper with a Harrison billet 6 which makes for good stopping now.
    All the parts shown in the excellent photos you have listed are exact copies of the Kyoto disc and fittings that I bought from Wemoto.I suspect there is ,once again a manufacturer who makes these parts that other companies such as Kyoto and Ferodo etch their names onto. It happens with woodworking machinery and other products so I don't see why bikes would be any different.

    Stash
    #20