100gspd Brake Upgrade

Discussion in 'Old's Cool' started by Crush, Jun 11, 2006.

  1. Crush

    Crush Been here awhile

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    Seems to me that I read somewhere that a left 4 pot caliper from an 1150gs can be adapted to the 100gspd to improve the front brake. I of course cannot find where I read that. I have read the various threads about using a nissan or harrison calipers and the large rotor from MAP. I was just curious about the brembo off an 1150gs.

    Thanks, Dennis
    #1
  2. Spanish Bob

    Spanish Bob I dont know where I am.

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    Actually I think that they are from the K1100. They need to be machined a little to fit.

    I wouldnt contemplate putting very effective calipers on standard airhead GS forks. I know Jorge (Rubber Cow) really likes his, but i would get scared that the bike would "cross hers legs" under stress! Jorge knows more than me so...
    #2
  3. Rubber Cow

    Rubber Cow GS Dork

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    Um....gee.....thanks I guess but I'm think I'm better described as a "horrible warning" not so much as a "good example". :D
    I like my Harrison 6 pot and the MAP 300mm Rotor and the Galfer Green pads and the Galfer Stainless line....Everything but the MAP rotor came on the bike when I bought it used. It worked very well but the front end was a typical R100GS stock, mushy mess.
    I installed a Race Tech Gold Valve and upped the oil weights to 10 and 15 wt (rebound/compression) and all was good.

    I've set up three other GS with Race Tech FIRST, before any brake mods and I think that this is my preferred way to do it. The last bike I set up was Sarah's in Palo Alto....she weighs nothing and rides like a respectable citizen so the stock brake & rotor works fine for her. I did add a Galer stainless line at the same time as the Race Tech and the difference was very noticeable. My suggestion is that you start there and move on to better pads and then calipers and then rotors....
    Cheers,
    Jorge
    #3
  4. beemerphile

    beemerphile Long timer

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    I put two 4-pot early oilhead calipers on my R100RT and all that was required to fit it was to mill down the mounting surface enough to center the caliper on the disc. Not much milling was required and plenty of stock was left. I would think the same thing would work with the GS. The mounting holes were the same for the early oilhead and the stock Brembo. One that may work without modification is a caliper from an R100R. They had the 4-pot Brembos from the factory. I did have to change to a larger master cylinder (15mm) to get the action right. With a single caliper you may need a smaller one than mine did.
    #4
  5. GSPD750

    GSPD750 Adventurer

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    This has been posted in the past but here it is again. Following pic
    is a 4 pot brembo from a K1100RS on my '93 GSPD. I believe I had to mill 2mm off both the fork slider and the caliper in order to center it onto the rotor. Galfer SS brake line and Galfer Green brake pads further compliment it. I still need to upgrade to a 15 mm magura master cylinder which should compliment the braking even more.

    [​IMG]
    #5
  6. Spanish Bob

    Spanish Bob I dont know where I am.

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    Jorge - I will try to describe you better next time:D

    The race tech option sounds interesting - any web sites with info on this?
    The fork oil, the hoses and pads (I was thinking EBC HH - but Galfer would be good) plus progressive springs were on my list. I will keep thinking about the calipers!

    I´ve just bought a R100GS PD classic with 8k miles from 1995 and ridden it from Stuttgart to Barcelona this weekend and I can tell you the the brakes need to be refined a little!:lol3
    #6
  7. Rubber Cow

    Rubber Cow GS Dork

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    Here's a link to the AirHeads instal notes,Linky I can send you a word doc that I put together several years ago.
    If you install the Race Tech I'd suggest that you stay with the stock springs. Progressives plus the Race Tech make the front end way too stiff.
    The Gold Vale is a cartridge emulator and is sold in pairs...You only need one for the R100 forks as only one leg of the forks deals with compression damping while the other is for rebound damping. Race Tech Europe
    might be of some help but your best bet would eb to see if any Advriders here in the states want to split a pair with you.
    Cheers,
    Jorge
    #7
  8. jellycow

    jellycow Back on track!

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    Okay, to bad these sites are in German but have a look at the pictures
    http://http://www.powerboxer.de/index.php?option=com_content&task=view&id=162&Itemid=145
    They use the leftside pot of a r100r, which is the same as most brembo 4 pots, eighter 2V-R, K of 4V-R.
    Take a look at ther picture #2 showing how the disk will not be aligned with the pot, some machining has to be done... A good solution for this is upgrading the disk to a HE one, http:/http://www.he-motorradtechnik.de/
    (Look under BREMSE, scroll a bit to the first one you see, it's on a GS) they are 320mm and add a lot of stopping power to the standard pot as well. These disks come with a large spacer to fit between the wheel and the disk itself, if you take of 4.5 - 5 mm from this spacer it'll will fit without having to destroy eighter your fork-leg or the pot itself.
    I use this combination and am very happy about it :D There is no need to change the master cylinder as far as I'm concerned.


    clement
    #8
  9. Rogue Scout

    Rogue Scout Instigator Deluxe

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    Stuttgart to Barcelona. There's a ride not everyone gets to do.
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  10. Rogue Scout

    Rogue Scout Instigator Deluxe

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  11. Spanish Bob

    Spanish Bob I dont know where I am.

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    What can I say Im a lucky man!

    I will look at this is detail -I need to get the bike re registered first before I start playing around or the the men from TÜV barcelona might get me!

    bob
    #11
  12. datchew

    datchew Don't buy from Brad

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    on the brake upgrade note:

    I've been wondering if it's possible to take the double rotor system, i.e., the entire front fork and all from an r100r and swap them out onto a gs.

    Looks like that's be alot easier if you could get one that's being parted out.

    I suspect if this was that easy, i'd have heard of it by now... but it never hurts to ask.
    #12
  13. jellycow

    jellycow Back on track!

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    Sorry, noob :rolleyes thought they worked..
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  14. datchew

    datchew Don't buy from Brad

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    Which is it?

    A - nobody ever thought of this and they're busy pondering
    B - The post # snobs decided I'm too much of NoOb to merit an answer
    C - It's such an old topic they think it's a joke.



    #14
  15. RocketJ

    RocketJ Been here awhile

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    Yes it would be easy. Bolts right up.
    Only 5 3/4" travel and about 5 " shorter overall.
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  16. Rubber Cow

    Rubber Cow GS Dork

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    Ouch! Howdy NoOb....welcome to Advrider!....for more of that, scroll down south and have a peek into JoMomma!:D
    #16
  17. datchew

    datchew Don't buy from Brad

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    he he he.
    That's MR noob to you. :D

    That's quite a bit of lowering on the front end.

    Is the difference in length due to the (sorry bout the terminological shortfalls) upper tubes or the lower "female" housing?

    If it's just the upper tubes that bolt into the steering hub (triple clamp?) then could you just swap out the lower end?

    p.s. will pass on Jo Momma. It's pretty dark and smelly in there.
    #17
  18. RocketJ

    RocketJ Been here awhile

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    [​IMG][/URL][/IMG]
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  19. Rubber Cow

    Rubber Cow GS Dork

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    :thumb
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  20. datchew

    datchew Don't buy from Brad

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    RocketJ.

    Can I then assume that was originally a standard gs?
    Cause i thought the gs's had black frames and black cylinder guards and that the R100R had a silver frame and better brakes.
    you've got some chrome on there, so i'm not sure.


    What do you think about my question about which portion of the fork tubes account for the change in length and their interchangeability (is that a word?)
    #20