First, I was referring to threshhold braking, which by definition is used to get the maximum stopping power without locking a wheel (the threshhold of a skid). The inital post on this thrread was from a rider confronted with a sudden, and unexpected need to stop to avoid a collision. Suddenly, you've introduced the subject of moderate braking. Nonethelss, a locked wheel still must be handled the same way. If you've not hear the phrase "rrelease immediately and properly reapply" regarding a front wheel lock up, you should seek training. Regardless of how many tears of riding you've done, you lack exposure to one of the most basic tenets off motorcycle operation.

Second, you're dealing with how you perceive friction to work, not how years of study have proven it works. The fact is once a wheel locks and begins skidding, if braking pressure is held steadily, the skid will continue. There are several related reasons, one is that you would take far more force to break the grip between the friction material and disc (or rotor) from locked, than it would allow before locking. Another is that once a tire begins a slide (skid), it is immediately generating a tremendous amount of heat, and this resuls in a shedding of both rubber compound from the tire, and oils from the pavement surface. This is also the reason a car skidding to a stop has a greater braking distance than a car stopped using threshold braking. You can learn more about this than you'd ever want to know by reading a book called "Trafic Accident Investigation Manual", published by the Northwestern University Center for Public Safety (formerly the Northwestern University Traffic Institute), by J. Stanard Baker.

Finally, as I apparenlty did not make clear above, ABS does function by releasing the brakes momentarily. This is of course disconcerting, but it is far better at it than a human could be; and again, it is the only way to return a wheel from a skid back to rolling friction. However, when you or I take an action, we know exactly what's going on. When ABS is doing it's thing, it only asks that you hold pressure on the lever/pedal to work at the best possible efficiency.

I guess if you're really convinced that you're better off witout ABS, you should not have it on your vehicle. However, I don't know a single expert rider who would forgo ABS on a vehicle upon whcih it was offered. As long as you brake properly, you will never even know ABS is there.

Harris
Denver, CO

www.youtube.com/conedown

 

I'm not sure mine works. I've slid the back tire before. I have felt the brake let go...is that abs in action? I have never felt a flutter in the brakes like when in a car. Do the peddles flutter?

 

No I never said that I was convinced to be better off without ABS, and your responses come across as condescending. I don't think that's necessary. You clearly don't understand what I'm describing most likely because YOU don't have the experience level. I'm not talking about threshold braking, not talking about cars skidding to a stop and melting the tires etc.

I could go ahead and repeat again what I've already said 3 times but I'm sure it wouldn't make any difference.

For the benefit of others, I've described a scenario where there is a pitfall to the ABS system.

Maybe I'll mount some onboard cameras, and write a white paper to document the problem with video evidence. It would be a good project, that way it would be open to experts to learn from as well.

 

I apologize if I was condescending. It certainly wasn't my intent.

I do hear what you're saying about the sensation that ABS creates. Having the machine release the brakes - even for a moment - is disconcerting. ABS is a case where the "least bad" option is employed. The goal is to allow the highest amount of braking the surface will support, and at the same time never allowing a locked wheel to occur. ABS balances these two competing goals very well, and better than a human can under the uncertain and variable conditions we encounter in the real world.

There are characteristics of ABS that are less than desirable. The best way to deal with those is definitely by deliberately engaging your machine's ABS under controlled conditions, so you can learn what happens in different cases, and anticipate what will take place.

The next generation of motorcycle brakes is liable to be something along the lines of the Bosch eCBS (Electronic Combined Braking System). I expect this to start showing up in a big way, in the next few years. My understanding is that this system will endeavor to use all inputs (which brake is used, braking effort, engine speed, vehicle speed, etc.) to divine what the rider is trying to do, and brake accordingly. From what I've seen of this, I'm not sure if I'm thrilled or not; but it will be something new for all of us to learn about.

Harris
Denver, CO

www.youtube.com/conedown

 

I hadn't heard about eCBS before. Hopefully they get it right.

I learned something from you today. I've never actually actuated the front ABS, based on what you've said here in this thread you've inspired me to go ahead and give it a try.

Thanks.

 

It does NOT take longer to stop with ABS if you consider that if it kicks in, you've made a mistake, and without it, you'd be in an accident.

 

Agreed. This is a common misconception, in practical terms, it goes something like this:

- moderate braking = the same for ABS vs. non-ABS bike because the ABS hasn't activated. In this circumstance both bikes behave identically since both have the same braking system.

- heavy/threshold braking = slight advantage to the non-ABS bike for the 1% of riders capable of perfect threshold braking.

- panic braking (ABS activated vs. non ABS skidding) = major advantage to ABS bike in both stopping distance and control.

Dave

 

It's well worth playing with, first on a good surface, and then on some not so good ones. You'll notice quite a difference in the strength of the feedback in the lever, on a poorer surface, but it will still be there.

If you find a surface like sandy dirt or grass, and you want to give it a try, it will feel very much like no brakes at all, since there's so little friction available. Keep in mind on those poor surfaces, the stopping distance my be longer than you anticipte, so go slow, and think about ditches, structures and the like.

Harris
Denver, CO

www.youtube.com/conedown

 

Pre-Zactly!

 

For riding on a public road, were the surface is changing every foot you travel, you will not be able to thresh hold brake as well. On a closed course, with a known conditions, thresh hold braking works great.

ABS is not prefect, you still must know to use your brakes, but I would much rather have the ABS, knowing it's short comings.

I think a lot of riders assume ABS is the save all, end all of using their brakes. They never learn how to properly brake a bike, ****, there are still many riders that believe in using the rear brakes only. I work with a guy that has gone through 3 sets of rear pads and is still on the factory front pads.