Results 1 to 11 of 11

Thread: ABS questions

  1. #1
    Kbiker BCKRider's Avatar
    Join Date
    Jan 2009
    Location
    B.C. Canada
    Posts
    744

    ABS questions

    Thought answers to the following questions by the more informed and experienced out there might help others as well as myself get the most from this expensive, but possibly life-saving, device.

    1. How does it work? In other words, when you apply force which would normally lock a wheel, does ABS rapidly lock and un-lock the wheel - a series of mini-skids, or does it reduce the braking pressure just before the wheel skids?

    2. How have succeeding generations of ABS changed? (Mine is I believe the earliest type on a 1992 K100RS.) Are later generations more effective in producing short stops? Sound or feel different? More or less trouble free?

    The following questions are for straight ahead stops, not when leaned over in a curve, where I gather ABS can get "confused:"

    3. In an emergency (deer darts out from the bushes) should you still use the "quick squeeze" to load the front tire before applying maximum pressure or is the "four-finger grab" more effective? (Has anyone measured this?)

    4. It would seem that hard braking on the rear wheel (big no-no with conventional brakes) would allow one to get the most stopping power from that end with no downside. Any comments?

    5. How do you recommend practicing using ABS on a bike? I think cowardice - or more kindly, a healthy sense of self-preservation - keeps many of us who do practice quick stops from getting the ultimate stopping power from our front tire with conventional brakes. There is a fine line which we don't want to cross, especially if we have done that a time or two. So, do we just need a wet piece of asphalt with no traffic and the courage to trust that really hard braking won't have us stopping horizontally?

    Every year, when snow and ice first cover our roads, I make a point of doing a few low speed ABS stops in my car. The tendency is to ease up on the peddle when you hear those weird sounds and feel that pulse. Hard to make new learning counteract old habits; almost impossible without some (maybe quite a bit) of practice. My guess is that most car drivers don't take advantage of ABS when the chips are down.

    Since I now have it on my bike, I know I need to practice using it, if I am to use it effectively when that rare situation requires it.

    I invite your opinions on this topic.
    Doug
    1992 K100RS

  2. #2
    Curmudgeon At Large Bobmws's Avatar
    Join Date
    Mar 2003
    Location
    Astatula, FL
    Posts
    1,106
    Your bike ABS works just like that in your car, releasing pressure just before lockup.
    Having had an '89K with ABS and now an 'o4, the newer system seems to cycle faster and more smoothly.
    Find an empty dry lot to practice in initially. Get speed up to 25-30 mph and practice hard braking in your normal mode. When you have a good feel for the brakes, try hitting the rear brake pedal hard. Normally this would start to skid and slide out. You will feel the ABS engage and see that the bike stays inline. When you are comfortable with that fell, add the front brake. As your confidence builds you can increase speed and just hit both brakes full on.
    CAUTION!!!! The ABS stops working once speed drops below 4-5 mph and the brakes will lock up and slide the tires.
    Once you're comfortable with the feeling of the ABS working, go ahead and try it on wet pavement.
    Enjoy.
    Bob Weis
    '04 K12RS - Hannigan Hack
    www.earplugco.com

  3. #3
    Dum vivimus vivamus ted's Avatar
    Join Date
    Mar 2003
    Posts
    2,582
    One great yet commonly overlooked feature of ABS is the ability to safely STEER during a full ABS lock-up. I learned this late one night while zipping over a mountain ridge on West Virginia Rt. 33 - a pack of big raccoons decided to put themselves directly in my line through a blind and particularly tight left-hander, I grabbed everything and with the ABS chattering away at full steam, steered right in between two of them coming safely to a stop a few yards beyond. After that night I vowed to slow down while riding in WV at night, and to never own a bike without ABS.

    I never really practiced using it, it will kick in every once in a while (like the time I had to stop quickly on a sandy road while at Daytona Bike Week.) You will hear it and feel the quick pulses through the rear pedal and hand lever. It took me a while to get used to it and trust it, especially coming off a 600 Ninja that high-sided me at one point when the back brake locked and kicked the bike sideways.
    Last edited by Ted; 01-28-2010 at 03:00 PM.
    Ted
    "A good stick is a good reason"
    1994 K75RT
    Moto Pages

  4. #4
    God? What god? roborider's Avatar
    Join Date
    May 2007
    Location
    Raleigh, NC
    Posts
    2,059
    I practice my ABS on the RT in a parking lot. I, as stated, started with the rear brake. That's easy, it goes to ABS right away. Using the linked lever (both brakes), I never got the ABS to engage. The RT was stopping so quickly I just couldn't fathom using ABS on dry pavement from 30 mph, and I didn't want to try harder. That RT stops FAST.
    Rob C. , Raleigh, NC
    '10 R12RT, R90/6
    2007 CBR600RR & 09 V-Star
    Suzuki DR 350

  5. #5
    Small road corner junkie pffog's Avatar
    Join Date
    Apr 2006
    Location
    WNY, Further fron NYC, than 6 entire states!
    Posts
    2,069
    Once you assure yourself it is working, as others said start at medium speeds. Once you have confidence, go out and nail them at road speeds. I do that regularly on bike and in the car, dry, wet and icy roads. If you don't practice you will always be tentative.

    I still practice threshold braking, just to stay in practice, but do it with confidence knowing that fine line is a big cushion with ABS. Besides it is fun to see just how FAST you can stop!

  6. #6
    God? What god? roborider's Avatar
    Join Date
    May 2007
    Location
    Raleigh, NC
    Posts
    2,059
    I'll have to play with mine more. I need a strap to connect my butt to the rear deck to I don't fly through the windshield.

    I rode an R100CS last year for several days. Bikes have improved a lot, but damn, braking is CRAZY good now on these machines.
    Rob C. , Raleigh, NC
    '10 R12RT, R90/6
    2007 CBR600RR & 09 V-Star
    Suzuki DR 350

  7. #7
    Kbiker BCKRider's Avatar
    Join Date
    Jan 2009
    Location
    B.C. Canada
    Posts
    744
    Thanks for some great advice!

    bobmws - your note (in red!) that ABS does lock up at low speed should be more widely known. Be a shame to make a perfect "panic" stop and then fall over because you forgot to ease up on the front brake lever at the end. Did that with my pre-ABS bike at a stop sign on a wet road. Would hate to make the same mistake again because I expected something the system was never designed to deliver.

    pffog - I think your advice for both cars and bikes - build up to road speed as you gain confidence - and practice under all conditions (ice on a bike?!!) is spot on.

    Another advantage of ABS not touched on yet is to check out just how slippery that wet backroad really is. If modest braking is activating your ABS, you have your answer as well as a strong suggestion about following distances and cornering speed. (Won't go into how I learned this.)

    Ted - glad you avoided those racoons. One of the car accidents ABS got me out of involved driving slowly down a very icy hill and finding cars broadside in both lanes, but fortunately staggered with no on-coming traffic. I had time to think "hey, you can steer with ABS." So I steered around the car in my lane and then back into my lane. No drama. But the $1000 extra ABS in my 1991 Subaru cost me was more than paid back that day.

    Your experience of using ABS when leaned over and then making steering changes is, I'm pretty sure, a new idea to most riders. Might I suggest that either you or pffog start a new thread about braking in the corners with ABS? If you do, I'm sure it will be a controversial and thought provoking thread; the best kind.
    Doug
    1992 K100RS

  8. #8
    haughty
    Guest
    Agrees with the new thread on cornering and ABS.

    ABS saved my Bacon. After that episode, I cannot imagine having a bike without it...

    Bikes from the 70s were so underwhelmed with braking power as to possibly enhance the problem with a panic stop...

  9. #9
    Alps Adventurer GlobalRider's Avatar
    Join Date
    Mar 2003
    Location
    Canada and the Alps
    Posts
    3,596
    Quote Originally Posted by BCKRIDER View Post
    My guess is that most car drivers don't take advantage of ABS when the chips are down.
    You're right, they don't because they're frozen with their brakes locked up and that has me wondering...how does a person that is frozen manage to steer at that point...which of course was what ABS was supposed to enable you to do at least according to all the TV commercials at the time when ABS first was offered.

  10. #10
    Alps Adventurer GlobalRider's Avatar
    Join Date
    Mar 2003
    Location
    Canada and the Alps
    Posts
    3,596
    Quote Originally Posted by BCKRIDER View Post
    Your experience of using ABS when leaned over and then making steering changes is, I'm pretty sure, a new idea to most riders. Might I suggest that either you or pffog start a new thread about braking in the corners with ABS? If you do, I'm sure it will be a controversial and thought provoking thread; the best kind.
    Well if you say it is possible, make a video and post it on YouTube of an ABS equipped bike with the front brake lever fully pulled back (ABS will be activated) while leaned right over.

  11. #11
    Registered User
    Join Date
    Nov 2007
    Location
    Joplin, MO
    Posts
    932
    Quote Originally Posted by GlobalRider View Post
    Well if you say it is possible, make a video and post it on YouTube of an ABS equipped bike with the front brake lever fully pulled back (ABS will be activated) while leaned right over.
    peoples definitions of turning and steering differ.

    If the bike was upright going straight and during an emergency stop with abs activated the rider steers and leans 10 degrees or so, I have every confidence the abs could adapt and allow the intended outcome.

    If the bike were well leaned over taking a corner at aggressive speeds, I have every confidence the ABS would be unable to save the rider from sliding out.

    IMHO it is a valuable tool, with rules of safe operation just like any other tool.

Posting Permissions

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