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Out-braking the ABS myth [video]

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Re: Out-braking the ABS myth [video]

#21

Post by rqtwteye »

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 far as driver training goers, a little training in sliding would also be very helpful so people know what to do when the car has understeering or oversteering.

Re: Out-braking the ABS myth [video]

#22

Post by tomtheelder »

Swizec wrote: post #9

FortNine is great but the conclusion in this video is a little silly. The best result comes from threshold braking with ABS enabled. Yeah no shit. As described in the video, motorcycles perform funny under braking. If you slam the brakes too fast, you have very little grip. ABS kicks in and you’re not stopping. If you progressively brake correctly, you transfer load to the front tyre and increase grip. ABS kicks in,…

I'm confused by which part of the conclusion you thought was silly. It seems like you reached the exact same conclusion than the video did, and I don't think it's at all obvious to most people that you are still supposed to threshold brake with ABS.

Re: Out-braking the ABS myth [video]

#23

Post by iokanuon »

tass wrote: post #19
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 a modern ( In the past, this was likely true when ABS systems weren't able to control individual wheels. They can do that today, can check for wheel lock-ups and react dozens of times a second, and can therefore compensate for changing grip at different parts of the road during the entire stopping process. In formula 1, where ABS has been banned, drivers have the capability to manually adjust brake balance (front/…

This video is about motorcycles, not cars. Also, the data on this is in the linked video - the author demonstrates you can do a controlled stoppie to decelerate faster without ABS, because that's its main feature - preventing you from flying off the bike.

Re: Out-braking the ABS myth [video]

#24

Post by jgalar »

chris_st wrote: post #11
Temporary_31337 wrote: post #2

The video correctly explains that ABS isn’t about shortest braking distance but more about a predictable trajectory and ability to avoid obstacles where possible. It also takes a lot of guesswork from braking as you can simply instinctively slam the brakes and get good enough results. Especially on a motorcycle slamming the brakes in panic without abs ends up in a crash.

Two experiences of mine: Braking on snowy/icy streets. First, in a car without ABS, I put on the brakes (I was probably going a little too fast) to avoid hitting the car stopped ahead of me. I started to slow down, but also to slip to the right towards the curb; it was scary, and I barely slowed down in time to avoid either collision. Second, in a car with ABS, I slowed down to turn into a parking lot, and the ABS ki…

My worst close-calls were a result of ABS engaging at very low speed. In all cases, I reduced the speed to 2-3 MPH approaching a snowy intersection, but the car refused to let the wheels lock and "sink" in the snow.

Instead, it's all too happy to drift into oncoming traffic at a glacial pace. It could be specific to the various Toyotas I have owned...

Re: Out-braking the ABS myth [video]

#25

Post by sudosysgen »

Swizec wrote: post #9

FortNine is great but the conclusion in this video is a little silly. The best result comes from threshold braking with ABS enabled. Yeah no shit. As described in the video, motorcycles perform funny under braking. If you slam the brakes too fast, you have very little grip. ABS kicks in and you’re not stopping. If you progressively brake correctly, you transfer load to the front tyre and increase grip. ABS kicks in,…

The average car doesn't actually have more grip than the average motorcycle.

More surface contact != More traction.

Grip in a motorcycle is only really limited by gravity. That's still far better than most cars. The average motorcycle (or bicycle, for that matter) will have little problem hitting 35 degrees lean and therefore produce lateral G forces exceeding that of a typical car.

Same is true for deceleration, the average bike is going to be able to slow down as fast or faster than the average car, even if you just let ABS takeover.

Motorcycles don't have any disadvantage in grip unless you're comparing them to the supercars that have significant downforce.

It really does come down to practice. The machine itself is more than capable. Even a cheap entry level motorcycle is eminently more capable in terms of braking and corner than many sports cars. The cool thing about have two tires, is that you don't need a super fancy suspension setup to be able to corner fast, you just need good tires.

Re: Out-braking the ABS myth [video]

#26

Post by chris_st »

jgalar wrote: post #24
chris_st wrote: post #11

Earlier quoted context omitted.

Two experiences of mine: Braking on snowy/icy streets. First, in a car without ABS, I put on the brakes (I was probably going a little too fast) to avoid hitting the car stopped ahead of me. I started to slow down, but also to slip to the right towards the curb; it was scary, and I barely slowed down in time to avoid either collision. Second, in a car with ABS, I slowed down to turn into a parking lot, and the ABS ki…

My worst close-calls were a result of ABS engaging at very low speed. In all cases, I reduced the speed to 2-3 MPH approaching a snowy intersection, but the car refused to let the wheels lock and "sink" in the snow. Instead, it's all too happy to drift into oncoming traffic at a glacial pace. It could be specific to the various Toyotas I have owned...

Technology is defined as that thing which almost works correctly.

Sorry to hear you had that experience! I've lived places where the "sink into the snow" was the right thing, but where I live now, there's very likely ice under the snow, so it's not clear if that would help.

Re: Out-braking the ABS myth [video]

#27

Post by jabl »

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.

I learned that 'pumping' is what you do to counteract the brakes overheating when going down a mountain and engine braking isn't sufficient.

Re: Out-braking the ABS myth [video]

#28

Post by [deleted] »

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…

[deleted]

Re: Out-braking the ABS myth [video]

#29

Post by david_acm »

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 believe the term "pumping the brakes" refers to applying and releasing pressure on the brakes. With ABS off, a tire that's locked up (not spinning) will stop in a significantly longer distance than one that's at the limit of grip (slipping with a slight under-rotation).

Assuming you have exceeded the limit of grip of the tires with the initial brake bite and the tires have started to lock up, by releasing and reapplying pressure you allow the tire to spin up again to regain grip and then apply more brake to help stop the car. I assume this was to kinda emulate what ABS is meant to do (albeit much slower?) but I never knew this was a thing until recently.

You do not need to pump the brakes if you can threshold brake, though I understand the fact that the vast majority of drivers on the road cannot do this and ABS is a life-saving fallback.

Also to add to your comment about everyone taking some time to practice. I would also 100% recommend a good racing simulator if you or a friend you know has one. Specifically a setup that has a load cell braking pedal. Most entry-level sim pedals are potentiometers which measure the distance your foot travels as opposed to a load cell which measures the force applied on the pedal. This is how my younger self learned to threshold brake (among other things) and I was surprised at how it all transferred to the real world when I finally hit the track later in life.

Re: Out-braking the ABS myth [video]

#30

Post by saalweachter »

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…

There are a lot of knock-on effects.

For instance, a lot of drivers prefer to swerve rather than brake ... because they're afraid of getting hit from behind, because everyone is tail-gating.

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