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Out-braking the ABS myth [video]

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Re: Out-braking the ABS myth [video]

#121

Post by the_sleaze9 »

Swizec wrote: post #44
sudosysgen wrote: post #25

Earlier quoted context omitted.

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…

The biggest problem for bikes when it comes to grip, in my experience, is that there is no redundancy. You brake hard, rear grip goes to zero, and you fishtail. Then you have to reduce braking force or you crash. This doesn’t happen in a car because unloading 2 independent tires is very hard. You touch loose gravel going through a corner, front loses grip, you crash. Hitting the same gravel patch with 2+ car tires is…

I learned in training to trust your motorcycle to keep it's footing when you encounter quick losses of traction.

They had a bike that was equipped with a roll-cage, like an exoskeleton that prevented it from actually flipping but did allow it to lay over enough such that it would. Then they sent the bike through excessive lean angles across slippery surfaces.

The riders who adjusted for the slippage wrecked, the ones who just allowed the bike to fish a little didn't.

Of course that's assuming you aren't too close to the threshold, etc.

But it was eye opening to learn to just kind of hang on and trust the machine a bit.

Re: Out-braking the ABS myth [video]

#122

Post by fiddlerwoaroof »

RandallBrown wrote: post #106
Night_Thastus wrote: post #81

Earlier quoted context omitted.

What's interesting to me is that in emergencies, apparently many people don't brake hard enough. So now they've created brake-assist options that try to determine when such a case is occurring, and slam on the brakes as hard as the car is able. As incredulous as that sounds, it's apparently improved overall safety. From what I've read the tech has been around since the 90's but has become much more standard.

I've never been in a situation where I didn't brake hard enough, but I'm a little surprised that's possible. I figured the amount of pressure required to lock the wheels was fairly minimal.

On modern cars with ABS you can’t lock the wheels, can you?

Re: Out-braking the ABS myth [video]

#123

Post by fiddlerwoaroof »

pintxo wrote: post #63
dsego wrote: post #59

Earlier quoted context omitted.

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.

I‘ve certainly done it, both on the street as well as in training settings.

I’ve definitely felt this when hydroplaning in Houston

Re: Out-braking the ABS myth [video]

#124

Post by whartung »

taylodl wrote: post #67

FortNine on HN! I love it when two different aspects of my life collide! For the HNers who don't know much about motorcycles, in the motorcycling world there's a big argument whether ABS is a net good or not. The old-timers tend to say "learn to ride your bike, you can beat ABS." Manufacturers site statistics saying ABS saves lives. This video is good in that it shows old-timer braking + ABS gives the best of both wo…

> That's why it's critical motorcycle riders practice emergency braking. You have to practice it enough to make it muscle memory.

Indeed threshold braking (which is what this is) is a very important skill to practice for a motorcycle rider.

However, that said, while folks can practice the maneuver, what is very difficult to practice is the situation. It’s one thing to practice on a dry parking lot in front of a cone or tennis ball.

It’s quite another to practice on the street in a crummy intersection with an F-150 turning left in front of you.

It’s always important to have data like this, talking about limits of systems, our role and impact as riders with such systems. This is a good video (all of Ryan’s stuff is excellent).

But I have seen others actually advocate switching ABS off, and I think that’s a bit irresponsible. Off road is a different problem, and a complicated environment for an ABS system. The track is another controlled space where folks can test limitations. Many bikes offer the ability to disable ABS systems (as a first class concept) just for these reasons.

But neither of those are the street. There are a lot of situations where straight line stopping is not necessarily the correct response. ABS is a boon in more cases than it’s not when it comes to emergency maneuvers.

The street is complex and unforgiving. Anyone who’s been in the community for any length of time knows about very skilled, even professional, riders that the street has taken from their families.

I love motorcycles and riding. I have for a very long time. And my simple rule is I don’t recommend it to anyone. It’s very dangerous. As riders, these systems are excellent, and get better every year.

Practice threshold breaking, by all means. Practice everything. But on the street, you need every edge. Leave your ABS on.

Re: Out-braking the ABS myth [video]

#125

Post by Night_Thastus »

fiddlerwoaroof wrote: post #122
RandallBrown wrote: post #106

Earlier quoted context omitted.

I've never been in a situation where I didn't brake hard enough, but I'm a little surprised that's possible. I figured the amount of pressure required to lock the wheels was fairly minimal.

On modern cars with ABS you can’t lock the wheels, can you?

You can't.

Re: Out-braking the ABS myth [video]

#126

Post by whartung »

bdsa wrote: post #46
doubled112 wrote: post #17

Earlier quoted context omitted.

This is quite literally called "the moose test" is it not?

The moose test is more of a slalom around an object, and tests (sort of) stability rather than braking

A testament to modern control systems in cars.

When the 2014 Jeep Grand Cherokee was released, it was an early release in mid-2013.

And, yes, it was an early release. The first month or so of models had all sorts of problems. And one of them was that the stability control system was not dialed in.

You can hunt down early video of the vehicle not doing well in the moose test. It does the swerve, but practically loses control. It’s rather horrific.

Later, they updated the systems and it performs the same test much, much better.

Most of these systems and what they do for day to day drivers is invisible. Watching the Jeep fail, and then later succeed, just shows how capable those systems really are.

Re: Out-braking the ABS myth [video]

#127

Post by toast0 »

jakeinspace wrote: post #95
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…

I got into my one and only accident less than a year after getting my first car, when another driver ran a stop sign. I was the one who tee-boned them, because they actually accelerated quite quickly out of the stop while I was going about 50 mph with right of way on a feeder road. I still can’t shake the feeling that I under-braked, although I did see some solid tread marks before the point of impact on the road. I…

Without knowing the conditions, since you seem to be asking for internet quarterbacking (please feel free to ignore if not)...

Braking harder may have also applied maximum braking sooner, or you may have been able to get tread marks on all wheels instead of only some wheels.

Also, as a more experienced driver, I definitely have fewer expectations that other vehicles will stop when they're supposed to. If you had visibility of the vehicle before it blew the stop sign, you may have been able to predict and slow down sooner or take evasive action.

Re: Out-braking the ABS myth [video]

#128

Post by Swizec »

the_sleaze9 wrote: post #121
Swizec wrote: post #44

Earlier quoted context omitted.

The biggest problem for bikes when it comes to grip, in my experience, is that there is no redundancy. You brake hard, rear grip goes to zero, and you fishtail. Then you have to reduce braking force or you crash. This doesn’t happen in a car because unloading 2 independent tires is very hard. You touch loose gravel going through a corner, front loses grip, you crash. Hitting the same gravel patch with 2+ car tires is…

I learned in training to trust your motorcycle to keep it's footing when you encounter quick losses of traction. They had a bike that was equipped with a roll-cage, like an exoskeleton that prevented it from actually flipping but did allow it to lay over enough such that it would. Then they sent the bike through excessive lean angles across slippery surfaces. The riders who adjusted for the slippage wrecked, the ones…

Yep this works great until it doesn’t. When I crashed after hitting a gravel patch it literally felt like a video game that skips a frame. My thoughts were “Gravel!” “Wait am I on the ground?” And a few moments later I stopped tumbling. There was zero time for a reaction of any kind. Happened so fast I didn’t even get an adrenaline rush out of it.

Luckily insurance paid for bike damage and new gear. I only got a bruise where my elbow missed the elbow pads. Bike stopped maybe 50ft down the road.

Re: Out-braking the ABS myth [video]

#129

Post by kimixa »

lmm wrote: post #118
kimixa wrote: post #91

Earlier quoted context omitted.

It definitely is as part of the UK driving test, though they normally tell you it's coming up and intentionally take you to a quiet back road and make sure it's completely empty first. In my test the instructor told me to keep driving until they wacked their clipboard on the dash, then I had to STOP as quickly as possible, and you'd fail if you didn't apply heavy brakes quick enough. And as this is common in the test…

It used to be a mandatory part of the UK driving test. Now it's one test out of three, so you can skip preparing it and just retake your test if you get unlucky.

~10 years ago they said they "may" do one, but every one of my friends was required to. I guess it might have changed since then? Or location dependent - I know different areas have different roads, in a reasonably-sized UK city (top 20 by population) the local instructors generally knew the 4-5 routes the local DVLA normally tested around, and intentionally practiced in those areas with the specifics they entailed. And speaking to people who tool their test in different cities the things that tended to be difficult and likely to catch them out were often different.

And having done the California driving test a few years back as well, comparatively the US one was pretty trivial in comparison. And I've heard the CA test is one of the harder ones in the states.

Re: Out-braking the ABS myth [video]

#130

Post by lmm »

kimixa wrote: post #129
lmm wrote: post #118

Earlier quoted context omitted.

It used to be a mandatory part of the UK driving test. Now it's one test out of three, so you can skip preparing it and just retake your test if you get unlucky.

~10 years ago they said they "may" do one, but every one of my friends was required to. I guess it might have changed since then? Or location dependent - I know different areas have different roads, in a reasonably-sized UK city (top 20 by population) the local instructors generally knew the 4-5 routes the local DVLA normally tested around, and intentionally practiced in those areas with the specifics they entailed.…

> ~10 years ago they said they "may" do one, but every one of my friends was required to. I guess it might have changed since then? Or location dependent - I know different areas have different roads, in a reasonably-sized UK city (top 20 by population) the local instructors generally knew the 4-5 routes the local DVLA normally tested around, and intentionally practiced in those areas with the specifics they entailed.

Test instructors are told they should carry out the emergency stop on one third of tests at random, and that was the guidance at least as far back as 13 years ago ( https://www.adicpd.co.uk/dsa-dt1-standard-operating-procedur... has a copy from 10 years ago, see page 40). A FOIA response I saw showed numbers that align with that, so unless some instructors are doing the emergency stop and then falsely reporting they didn't...

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