Results 1 to 11 of 11

Thread: Occasional herky-jerky rear brake - 2000 R1100RT

  1. #1
    Registered User
    Join Date
    Apr 2012
    Location
    Los Angeles, CA
    Posts
    316

    Occasional herky-jerky rear brake - 2000 R1100RT

    Occasionally, when I'm using the rear brake only, and harder than usual, I'll get a kind of herky-jerky action happening. Don't know how else to describe it. It's very brief. When it's happened, I've backed off the brake, and probably engaged the front brake some instead. It hasn't happened often enough for me to have a patterned response.

    This is the only bike I've ridden with ABS. So is this just what the ABS feels like when it engages? When I've engaged ABS in cars, the pulsation is much more rapid and regular. This feels more uneven - but maybe that's the nature of ABS on a two-wheeled vehicle, or the relatively older ABS this bike has. Or is there some brake condition that can cause this?
    2000 R1100RT / 1987 K75C (RIP) / Santa Clarita, CA

  2. #2
    Benchwrenching PGlaves's Avatar
    Join Date
    Oct 2003
    Location
    "Big Bend" TX
    Posts
    8,614
    I suspect you are over-using the rear brake - activating the ABS - and feeling the result.
    Paul Glaves - "Big Bend", Texas U.S.A
    "The greatest challenge to any thinker is stating the problem in a way that will allow a solution." - Bertrand Russell
    http://www.bigbend.net/users/glaves

  3. #3
    Registered User dieselyoda's Avatar
    Join Date
    Mar 2013
    Location
    Winnipeg, MB, Canada
    Posts
    538

    ABS is awesome, used it today, cleaned my underwear afterwards.

    I haven't experienced a "Herky-Jerky" from my ABS but sure did on a Kawasaki Concourse with ABS. Heated the rear brake up with a good ride, rotor warped almost 0.012".
    1997 R1100RT (Restored Basket Case) , 1981 KZ 440 LTD (Restored Basket Case)
    1986 K75S(the beutch), 1993 K1100RS (blown engine), 1997 Chev Short Box (4x4 with an LT1)
    "You can easily judge the character of a man by how he treats those who can do nothing for him."

  4. #4
    Registered User Jim Rogers's Avatar
    Join Date
    May 2009
    Posts
    348
    +1 on what Paul said.
    Gear Up and Ride Safe
    Jim Rogers
    2010 R12GSA aka Heidi
    Yorktown, Va

  5. #5
    Registered User
    Join Date
    Apr 2012
    Location
    Los Angeles, CA
    Posts
    316
    Thanks, guys. My first thought was the ABS; it's just a very different sensation than I would have expected.
    2000 R1100RT / 1987 K75C (RIP) / Santa Clarita, CA

  6. #6
    MOA #24991 Pauls1150's Avatar
    Join Date
    Apr 2008
    Location
    south of Los Angeles
    Posts
    1,449
    It would still be worthwhile to inspect the pads' condition (especially the inner one that's harder to see from the rear: it wears faster), and also check the runout (warping) of the rotor.

  7. #7
    Registered User
    Join Date
    Apr 2012
    Location
    Los Angeles, CA
    Posts
    316
    Quote Originally Posted by Pauls1150 View Post
    It would still be worthwhile to inspect the pads' condition (especially the inner one that's harder to see from the rear: it wears faster), and also check the runout (warping) of the rotor.
    New brake pads are currently "out for delivery."

    The rotor is nearing (but not yet at) its wear limit. I haven't checked runout, and likely won't bother as I'll be replacing it within the next few thousand miles.
    2000 R1100RT / 1987 K75C (RIP) / Santa Clarita, CA

  8. #8
    Registered User
    Join Date
    Jun 2012
    Posts
    213
    Well, I knew what it was the first time it happened to me (on US129!), because I had experimented with the ABS out in the grass in the side yard.
    Never having had ABS on a motorcycle I was not sure at all I liked the idea.
    I didn't want to get rattled the first time they engaged.
    Yeah, the neighbors thought that was a riot. I shoulda done it wearing my speedo.
    Well I got a little rattled, mostly 'cause I was wondering where the road went there for a second.
    ...this is great, the smokies... surrounded by beautiful TREES erk! (chatter, crowhop) whew.

    Anywho, if this happens to you on pavement with good traction then you're probably too dependent on the rear brake.
    Which comes naturally to those of us who learned to ride on 60's Japanese flexi-flyers with the treacherous double-leading-shoe drum front.
    You'll have to retrain yourself and learn to trust the bike's front end a little more.

    And since you mentioned brakes - am I the first on the thread to tell you to replace your brake hoses with stainless?

  9. #9
    Registered User
    Join Date
    Apr 2012
    Location
    Los Angeles, CA
    Posts
    316
    I learned to ride on a K75. And I'm still learning.

    I tend to favor the rear brake when moving (relatively slowly) through stopped or slow-n-go traffic on the 405 freeway to work, where I want quick transitions between brake and throttle.

    You are the first on this thread to suggest stainless lines, yes. Turns out, however, the lines were dealer-replaced within the last year, so no real urgency on this.
    2000 R1100RT / 1987 K75C (RIP) / Santa Clarita, CA

  10. #10
    Seattle-area Rounder OfficerImpersonator's Avatar
    Join Date
    Dec 2006
    Location
    Just north of Seattle, WA
    Posts
    2,806
    Check your ABS sensor ring for damage.

    The prior owner of my 2002 RTP sold the bike to me because he couldn't stand the "jerky/grabby" brakes. After a careful inspection of the braking system, I discovered approximately 3 cm of the front ABS sensor ring was deformed. The result was that the ABS sensor "reader" would encounter a brief skip in the sensor ring on every revolution of the wheel. This provided inaccurate data to the ABS system, and thus the brakes would "grab" and "jerk" when used.

    I was able to bend the ABS sensor ring back into its original shape, and the jerky brake problem instantly evaporated. If a bent sensor ring can do this to the front brake, I'm sure the same is possible on the rear brake.
    Seattle, WA
    2012 R1200GSA
    2002 R1150RT-P
    1992 K75S sold

  11. #11
    Registered User
    Join Date
    Apr 2012
    Location
    Los Angeles, CA
    Posts
    316
    Quote Originally Posted by OfficerImpersonator View Post
    Check your ABS sensor ring for damage.

    The prior owner of my 2002 RTP sold the bike to me because he couldn't stand the "jerky/grabby" brakes. After a careful inspection of the braking system, I discovered approximately 3 cm of the front ABS sensor ring was deformed. The result was that the ABS sensor "reader" would encounter a brief skip in the sensor ring on every revolution of the wheel. This provided inaccurate data to the ABS system, and thus the brakes would "grab" and "jerk" when used.

    I was able to bend the ABS sensor ring back into its original shape, and the jerky brake problem instantly evaporated. If a bent sensor ring can do this to the front brake, I'm sure the same is possible on the rear brake.
    Thanks, never would have thought of that. I'll check it out.

    I was all ready to change the rear pads & rotor this weekend, and found one of the rotor mounting screws stripped once I got the wheel off. So I changed the pads, which were definitely end-of-life, and left the old rotor on there. (It's still within the service limit.) At some point in the winter I'll probably have the bike in dry-dock for a week or so to do a spline lube and now, a bolt extraction. (And yes, new pads again with the new rotor.)
    2000 R1100RT / 1987 K75C (RIP) / Santa Clarita, CA

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •