How Valuable can ABS be??

[glider]

Whatever you say biglew

 

[09ultra]

This bone of contention between believers and non-believers in the ABS system is not limited to this forum, and the fact that a few experienced members are openly disagreeing is further evidence of a problem in the ABS system, in my opinion. If it was a proven fool-proof system with no errors, no one would argue about it. We don't argue about needing a headlight, do we?

The very fact we CAN argue is an indicator of an issue, again, just my humble opinion.

Good reply. I don't think anyone wanted to get a contentious debate going. Bottom line is the jury is out on ABS on HD. Glider has much experience and is much respected here. I take all he says and bank it. He has saved me many a time. I think ABS is a good thing and I am happy to have them. I do however see plainly the points Glider and others have made and they are valid as well. I do not think they are saying ABS is junk, just not for everybody. Somre cases they will help, others they may hinder. It is each of our choice and that is a good thing.:s Ride safe.

 

[09ultra]

Hobbit, an interesting and fact filled response to a hot topic....
I am concerned though, that I don't believe anyone would have to be a "braking god" to be able to heartily appreciate and put to life-saving use the advantage of an extra 15-20 feet in stopping distance. I myself have had to stop short just recently, and almost rear-ended a car as a result. I came to a stop (upright), just 3 feet from his rear bumper, and that 3 feet felt like 3 inches when I finally stopped with my heart pounding in my chest.

Important Note:

If I had ABS, does this mean I might have (just saying MIGHT here) continued traveling another 12-17 feet, which means I would have hit the rear of that car VERY VERY hard??

PPS: I better add that yes, I had the rear brake locked up and skidding, and hard, hard pressure (on the front brake) deliberately stopping just short of locking the front down, which I knew would take the scooter out from under me.

First of all I am glad you got stopped! I think you answered your own question: Since your rear was locked up and skidding, that would be the stopping difference with ABS. If you locked up your rear, then you were far from stopping as soon as you would have if you could have been able to brake perfectly, which would have had no locked up rear tire. The perfect scenerio you just gave. IF you could have braked perfectly with no locked up rear, then you out performed the ABS, the fact you locked up the rear would indicate ABS would have in fact stopped you even sooner. In a panic it becomes harder to brake perfectly as you experienced.

 

[wb4eje]

Good discussion! I might as well wade in here too.

I don't think the intention of ABS was to make the bike stop faster. As can be seen in the data, a Non-ABS bike can stop as short or shorter. But also consider that the data was collected in a test situation, out on the street is different.

With ABS you are actually trading a few percentage points of stopping distance for CONTROL. Consider that you are surprised by a cager pulling out in front of you and you have to make an emergency stop. All is fine until the rear wheel locks up and the bike starts to slide around on you. At that point you are getting little braking from the rear and if you maintain maximum braking on the front brakes, even countersteering the skid, the rear is just going to start coming around faster. You have lost control and braking distance is only now ONE of your problems. In this situation you can't get the maximum braking performance. The problem is that when you are surprised you can easily over brake and it doesn't take long for the rear of a Ultra to get loose, been there, done that, but didn't get the tee-shirt! Under a brake test condition with several tries to get the best braking distance, sure you can out perform the ABS systems. On the street, when the rider is suddenly surprised by a traffic condition, the ABS allows you to maintain control of the bike when you might not otherwise do so.

With ABS the rear doesn't lock up and swing around. You are able to maintain control and that gives you more options than being out of control in a skid.

My point is, without control, a couple of percent of difference in stopping distance really doesn't mean much!

 

[Merlynn]

Hey now, nothing personal here, I don't have enough experience to argue! Just trying to understand why some experienced riders would be skittish about this system. It's always a learning curve for me.

 

[NEWHD74FAN]

First of all I am glad you got stopped! I think you answered your own question: Since your rear was locked up and skidding, that would be the stopping difference with ABS. If you locked up your rear, then you were far from stopping as soon as you would have if you could have been able to brake perfectly, which would have had no locked up rear tire. The perfect scenerio you just gave. IF you could have braked perfectly with no locked up rear, then you out performed the ABS, the fact you locked up the rear would indicate ABS would have in fact stopped you even sooner. In a panic it becomes harder to brake perfectly as you experienced.

Some may be missing the point, the tire contact of both wheels are in play during the braking maneuver...if the rear is skating, there is NO braking out back, and it is essentially unweighted. ABS lets the rear tire patch remain in contact with the road assisting and adding to the rear braking, not just skidding, plus it levels the bike fore & aft, which lessens the load (overload) on the front suspension allowing marginal direction/steering control. 800-900 lbs of bike plus load on the front tire patch only, with bottomed out suspension is not necessarily a good thing if you need to add obstacle avoidance along the way!

There have been many bike tests with outrigger supports and test riders of varying skills and the results well documented that point ABS would be a positive benefit to most of us non professional riders in a "panic stop"...(meaning - not in full control)! ABS is a TOOL only, but it is no substitute for rider control = Practice-Practice-Practice...PERIOD! :14:

 

[NEWHD74FAN]

My concern is that in certain situations, "pumping the brakes", so to speak, is NOT enough. Yes, the element of control is definitely increased, as far as the bike NOT skidding, but an experienced rider can maintain the bike in a straight line as long as the speed isn't just too fast for that, (some speeds are just going to result in an uncontrollable slide no matter what...I am talking about manageable panic stops), and the front brake is effectively used. The ABS system will keep the bike straighter without such human intervention, but at a cost of some stopping footage that may be the difference between hitting a car or a tree or not.
Now if I am not right about my understanding here, I am absolutely open-minded about education and always willing to admit when I'm wrong, but right now, this is my understanding....so....am I wrong?

The key here is "-in a straight line..." what if more than one thing happens in this dynamic situation...accident prevention during a "panic stop" means additional inputs from the pilot may be required and such distractions will affect those decision(s) in a three dimensional world...:bigsmiley21: