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Out-braking the ABS myth [video]

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Re: Out-braking the ABS myth [video]

#51

Post by pintxo »

dsego wrote: post #38
rqtwteye wrote: post #21

Earlier quoted context omitted.

"In emergency situations I break with full force without hesitation. This has lead to multiple avoided crashes and TBH two back collisions. Once I pushed so hard the break light sensor had to be replaced." I think full braking should be part of driver training. A lot of people I know are very hesitant to brake full force and I think a lot of accidents happen because people don't really brake all out when needed. As f…

But it also requires some resolve when the abs starts pushing back on the pedal. The instinct is to lift your foot instead of fighting the pedal, which is what you should do.

I’d it normal for cars to do this? Never experienced my break Paddel to push back.

Re: Out-braking the ABS myth [video]

#52

Post by ehaliewicz2 »

rqtwteye wrote: post #21
j-a-a-p wrote: post #4

I did a anti-slip course where we learned dosed breaking to reduce break distance. And once a circuit racing course where the instructor just told me to break with all force available. The latter stuck. This instructor logic was, only if you are a pro driver you actually can outperform ABS. In emergency situations I break with full force without hesitation. This has lead to multiple avoided crashes and TBH two back c…

"In emergency situations I break with full force without hesitation. This has lead to multiple avoided crashes and TBH two back collisions. Once I pushed so hard the break light sensor had to be replaced." I think full braking should be part of driver training. A lot of people I know are very hesitant to brake full force and I think a lot of accidents happen because people don't really brake all out when needed. As f…

This might be a little too far, but I sometimes say to my friends that a minor crash should actually be part of driver training. Modern cars feel extremely safe, and nearly drive themselves, so many people do not take driving as seriously as they should, and not as seriously as they do after they have their first collision.

Perhaps being required to actually use 100% braking power to pass is enough :)

In this respect, motorcycle training courses are MUCH better, and have numerous braking and swerving drills, but they have to be, because motorcycles require a higher-level of attention and are significantly more dangerous to operate than a car.

Re: Out-braking the ABS myth [video]

#53

Post by ehaliewicz2 »

argiopetech wrote: post #10
briffle wrote: post #8

Earlier quoted context omitted.

Family Member is head of training for very large fire department. For testing their truck drivers, if they ABS kicks in at all, you fail the test. They want you to go all the way up to the limit, and ease off the breaks slightly as the 60,000lb truck gets close to kicking in its ABS.

This is called "threshold braking" (though it's often incorrectly called "pumping the brakes") and was/is standard practice for vehicles without ABS.

Pumping the brakes is what you do if you cannot threshold brake. You lose traction, so let off the brakes to regain grip, then apply again and repeat, hence pumping.

Re: Out-braking the ABS myth [video]

#54

Post by tass »

briffle wrote: post #18
justin66 wrote: post #12

Earlier quoted context omitted.

Is ABS a feature on their training truck that doesn't exist on the real rigs, or something? I've read about police receiving the opposite instruction: a reminder during training that they should keep their foot on the brake when they feel the ABS coming on. Apparently too many police were crashing because they'd lift, and attempt threshold braking as they'd been trained back in the day, when they felt the ABS coming…

All modern fire trucks have ABS. The ABS does allow better control if you break traction, but lenthens your stopping distance. They want their drivers to not break traction, and keep the stopping distance short. Big difference between a Subaru slamming into you because it couldn't stop fast enough, and a firetruck loaded with 1500 gallons of water, etc, slamming into you.

Have they done a side-by-side test? Or was that based on some information from years ago? If they don't break traction, how do they know they're braking enough?

If this is a modern ABS system I'd be shocked if they could beat it. See this short video comparing a 20 year old (at the time) vs modern semi-trailer weighing 38.5 metric tons (84,000 lbs). https://www.youtube.com/watch?v=Vo6C3HEpfsQ

Re: Out-braking the ABS myth [video]

#55

Post by dsego »

Hamuko wrote: post #45
dsego wrote: post #38

Earlier quoted context omitted.

But it also requires some resolve when the abs starts pushing back on the pedal. The instinct is to lift your foot instead of fighting the pedal, which is what you should do.

The instinct? I've never had that instinct since I've never driven a car without ABS for any extended period of time.

Right, but if the pedal suddenly starts pushing back, are you naturally expecting that? I was involved in three collisions where I failed to stop in time, and all three times the pedal pushed back. I didn't really expect it the first time. Talking about 90s and early 2000s cars, so not brake-by-wire.

Re: Out-braking the ABS myth [video]

#56

Post by timthorn »

JohnBooty wrote: post #13
j-a-a-p wrote: post #4

I did a anti-slip course where we learned dosed breaking to reduce break distance. And once a circuit racing course where the instructor just told me to break with all force available. The latter stuck. This instructor logic was, only if you are a pro driver you actually can outperform ABS. In emergency situations I break with full force without hesitation. This has lead to multiple avoided crashes and TBH two back c…

I got really good at pumping the brakes (is that "dosed braking"? new term to me) in the days before ABS. You can definitely get close to the performance of ABS with practice. Used to practice in the snow, in empty parking lots. (ABS or no ABS, everybody should safely practice recovering from spins and slides in empty parking lots! It's also really fun...) The idea that a pro could outperform ABS is surprising to hea…

> I got really good at pumping the brakes (is that "dosed braking"? new term to me) in the days before ABS.

I always understood the term was cadence braking; that might be UK terminology though.

Re: Out-braking the ABS myth [video]

#57

Post by dsego »

tass wrote: post #50
dsego wrote: post #38

Earlier quoted context omitted.

But it also requires some resolve when the abs starts pushing back on the pedal. The instinct is to lift your foot instead of fighting the pedal, which is what you should do.

With brake-by-wire, is this even necessary? I thought that ABS feeling occurred because the brake pedal was connected to the master cylinder, but isn't necessarily desired. My bike definitely pulses the brakes in a way that you feel on the controls, but they are directly connected to the hydraulics.

Oh sorry, this was my experience in 20-30 year old cars, they push back, so you need a firm hold on the brake.

Re: Out-braking the ABS myth [video]

#58

Post by ehaliewicz2 »

mindslight wrote: post #34

Is the default behavior in motorcycle land really to just use the back brakes? When I rode a bicycle in a city I learned to use both, but primarily my fronts. I definitely had some panic stops where I was modulating to prevent the rear wheel coming off the ground. But maybe the calculus changes with motorcycles' higher speed, as maintaining steerability becomes that much more important? I'm actually kind of surprised…

It's possible that really high end bikes (either sportbikes, or fancy tourers like goldwings) do, but ABS isn't really about maximum braking performance. It is about maintaining maneuverability during emergency braking (given that tires have a limited amount of grip, this is opposed to achieving the minimum possible braking distance).

>But maybe the calculus changes with motorcycles' higher speed, as maintaining steerability becomes that much more important?

It's just a panic response. Everybody on a motorcycle (hopefully) knows that you should be using front brake to slow down as quickly as possible, unless you need to swerve of course :)

Re: Out-braking the ABS myth [video]

#59

Post by dsego »

pintxo wrote: post #51
dsego wrote: post #38

Earlier quoted context omitted.

But it also requires some resolve when the abs starts pushing back on the pedal. The instinct is to lift your foot instead of fighting the pedal, which is what you should do.

I’d it normal for cars to do this? Never experienced my break Paddel to push back.

Have you tried slamming the brakes to avoid a collision? It's not something that happens in normal braking situations. Also, not sure if it's a thing on most modern cars.

Re: Out-braking the ABS myth [video]

#60

Post by tass »

dsego wrote: post #57
tass wrote: post #50

Earlier quoted context omitted.

With brake-by-wire, is this even necessary? I thought that ABS feeling occurred because the brake pedal was connected to the master cylinder, but isn't necessarily desired. My bike definitely pulses the brakes in a way that you feel on the controls, but they are directly connected to the hydraulics.

Oh sorry, this was my experience in 20-30 year old cars, they push back, so you need a firm hold on the brake.

No don't be sorry, I'm mainly curious if they still had the same feeling. I don't know the last time I had to brake hard enough to need ABS in the car, if they still had that feeling, or even if my car has brake-by-wire.
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