Re: ABS

[rene-didier@xxxxxxxxxxx]

Steve, your response is well written. ABS is great in a straight line. It is not a cure all for loosing traction. For the average rider ( not the top 1%) stopping distances will be shorter with ABS. I am on my 6th motorcycle, first with ABS, and it is really nice, especially in the rain ( I live in the Pacific NW, and can ride most days, as long as I don't mind the rain in the "winter"). I would not count on my ABS working when leaned over very far. The momentary lock up of the front wheel could let it slip out from under you. ABS is a nice safety measure. If you are using it often on the street, you might want to re-evaluate your riding technique.
"Stoppies" are still possible with ABS, and easily done. Just make sure you are going straight. I doubt many non-ABS riders feel comfortable doing "stoppies". I don't recommend them for stopping every time, but it is nice to know how they feel, and that it is not the end of the world when the rear wheel come a foot or more off the ground. Pulling in the clutch and grabbing all the breaks you can, in a straight line, will open your eyes to how fast you can stop, and the chattering of ABS working. The the R1100S, the front and rear break is controlled by the front break lever. No need, in this case, for the break pedal to be pushed. ( Rear breaks are nice for tightening lines in corners, or very slow speed ( less than 5MPH) breaking when turning.)

- -Rene
"02 R1100S w/ABS

- -------------- Original message -------------- 

> Hello Fritz, 
> 
> From: "Fritz Curtis" 
> 
> > I've been riding 25 years now plus one year on a Harley 
> > fifty four years ago. (lucky to get rid of that) 
> > I just bought a 2001 R1100RT-Police bike with ABS. 
> > For the first time in 25 years I nearly rear-ended a car as my 
> > attention wandered. I grabbed my brakes in a death grip and 
> > of course they did NOT lock up on me and I was able to steer 
> > around the stopped vehicles in front of me into the space 
> > between two lanes of traffic. Now here is my question. 
> > Is it possible to "lay the bike down" ? Is it possible to "high-side"? 
> > In my opinion these terms have become obsolete with the advent 
> > of ABS. In the twenty five years I've been riding, I figured if I ever 
> > locked up the brakes, I would surely "lay the bike down". 
> 
> I am a big fan of motorcycle ABS, so it may come as a surprise to many to 
> hear me say that yes, you can still "lay the bike down" or "high-side" it, 
> even with ABS. BMW does a good job in their user manual to warn riders that 
> ABS is ineffective in circumventing the laws of physics. 
> 
> Let's first talk about what ABS does. ABS is designed to do one thing, and 
> that is to prevent wheel lockup under certain conditions (it deliberately 
> turns off this function at very low speeds to let you come to an actual 
> stop). In doing so on a motorcycle, ABS helps to prevent skids that could 
> result in a loss of vehicular control and a subsequent incident. 
> 
> ABS works really well when the bike is traveling on a straight line, and the 
> tires have some traction. The more traction, the better. If, for example, 
> you apply your brakes on glare ice where traction is negligible, the brakes 
> will lock momentarily, ABS will dutifully release the brakes to allow them 
> to regain their grip, but there may be insufficient traction between your 
> tires and the glare ice to establish any sort of meaningful grip. I this 
> scenario, a skid could result, followed by loss of control and a possible 
> "lay down". 
> 
> In another scenario, imagine going around a moderate right turn very 
> quickly, really leaning the bike into the turn. The tires are near the 
> limits of traction. The rider, who did not exercise the best judgment, is 
> riding faster that his "line of sight" (i.e., he cannot stop within the 
> limits of his line of sight, or in other words, if a risk suddenly comes 
> into sight, he will not be able to stop before encountering that risk). As 
> the rider rounds the bend, he notices a slow-moving car entering from a 
> side-road. Without realizing that the tires have very little reserve 
> traction left, the rider taps his brakes causing momentary lockup. As ABS 
> dutifully kicks in to release the locked brakes, the bike has already 
> progressed its lean beyond the angle of recovery, and has low-sided. There 
> are many more real-world examples of low-sides, or "laying the bike down", 
> which may occur, even in much less extreme conditions, and in which ABS will 
> not be able to prevent a skid. 
> 
> Now let's talk about "high sides". A high-side is a scenario in which a 
> motorcycle's rear end looses traction in a turn, and the back end starts to 
> slide out from under the bike. The rear end the suddenly regains traction, 
> and violently rights itself, and in doing so, ejects the rider upwards, 
> possibly completely off the motorcycle into an airborne state. I am going to 
> steer clear of my own speculation on what ABS *may* do when braking into a 
> corner in which traction levels change suddenly from low traction (ABS doing 
> its job an barely keeping the bike from skidding), and then suddenly 
> encountering high traction mid-way through the turn. I will, however, depict 
> a scenario in which a rider is accelerating rapidly through a turn, is *NOT* 
> using his ABS brakes, and for some reason (sand, gravel, accelerating too 
> hard), the rear end breaks free. Without grip, the rear tire spins up faster 
> than the bike's speed and the rear end starts to go into a slide. The rider 
> detects this and lets off the throttle in the hope of recovering from the 
> low-side. In doing so, the rear-end "hooks up", and violently rights the 
> bike with such force that the rider is ejected upwards and is airborne. 
> 
> As you can see, even with an ABS-equipped bike, it is still possible to get 
> into a lot of trouble. Low-sides and high-sides included. That said, I still 
> feel strongly that: 
> o Motorcycle ABS is a good thing 
> o In most cases, it does the right thing 
> o On the street, in virtually all cases, riders are better off with ABS 
> than without 
> 
> I urge you to spend some time studying and learning what ABS does, and how 
> it does it. I'm sure that other members on this list will help out. By being 
> well-informed, you will have a better idea of how ABS can save your hide, 
> where it is less capable of doing so, and the scenarios in which ABS is 
> actually a detriment (if you are unaware of this, it will catch you by 
> surprise). 
> 
> -Steve Makohin 
> '01 R1100S/ABS 
> Oakville, Ontario, Canada 

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