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Dust from car brakes more harmful than exhaust, study finds

e360.yale.edu

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Re: Dust from car brakes more harmful than exhaust, study finds

#241

Post by carlosjobim »

amazingamazing wrote: post #27
digdugdirk wrote: post #25

Earlier quoted context omitted.

That's a great idea. And since it'll be limited to in town use, something narrower might be useful - maybe give it two wheels instead of four? That'd be huge for reducing weight and increasing range. And for suitable geographic areas, it might even be possible to make one light enough that it could be powered by the rider, no external power source required! Then, with the reduction in width required for these futuris…

You show me one of these that can be ridden [comfortably] in 2 degrees Fahrenheit with snow and ice everywhere and you have my money!

It's perfectly fine to have both a car and a motorcycle. Motorcycles are dirt cheap, so it pays for itself in gas costs pretty fast.

Re: Dust from car brakes more harmful than exhaust, study finds

#242

Post by scottbez1 »

steelframe wrote: post #82
bluescrn wrote: post #28

Earlier quoted context omitted.

Interesting that nobody every talked about tyre/brake dust until it became clear that cars aren't going away as we phase out fossil fuels, they're just going electric. Is this a serious environmental concern compared to the climate/emissions issue, or just the 'r/fuckcars mentality'? Meanwhile, here in the UK, one of the more interesting alternatives - personal light EVs (ebikes/scooters) are being utterly demonized,…

> very limited 250W/15mph pedelec class of e-bikes Meanwhile in the Wild West (a.k.a. the United States) we have children hurling 100+ lb 750W throttle-controlled motorcycles (I'm sorry, "e-bikes") at up to 28 mph on mixed-use pedestrian trails. The best we can do is put up plastic signs on the trail begging them to slow down and be careful around other people.

And yet, despite the wild west regulatory situation you claim, bicycles kill and injure way fewer people than cars, and don't require insurance because it's nearly impossible to cause the level of damage with a bike as even a minor fender bender in a car. And, even considering how "dangerous" bicycles are, studies have repeatedly shown them to increase life expectancy of the rider. Meanwhile cars are among the highest cause of accidental death of children of nearly all ages in the US.

Your argument is actually a strong one in favor of bicycle-favoring transportation policy: despite limited existing regulation they're still incredibly safe, and we can always tweak policy to handle the worst case exceptions as needed if they end up causing significant problems as bicycle share grows.

Re: Dust from car brakes more harmful than exhaust, study finds

#243

Post by NewJazz »

snozolli wrote: post #183
Schiendelman wrote: post #172

Earlier quoted context omitted.

Regenerative braking has much less tire wear than traditional braking because it's done much more slowly and smoothly. Also, none of these discussions use up-to-date information on EV tires. Consumers aren't willing to replace their tires much more often for an EV except at the high end of the market, tire manufacturers are already making tires last much longer for EV purposes. New designs are already shedding less d…

Regenerative braking has much less tire wear than traditional braking because it's done much more slowly and smoothly. Absent any evidence, I don't believe that claim. Unless you're skidding, I don't see how braking slowly and smoothly over a longer period causes any less tire wear than braking more rapidly for a shorter time. Additionally, since this is intrinsically tied to EVs, they weigh more and thus increase ti…

Slower braking is generally accepted to cause less brake pad wear. I was only able to find this article, but I'm sure more convincing evidence can be found if you do more research than the quick ddg and clicking on the first result I did.

Hard Braking: Less experienced drivers often react late to situations, slamming on the brakes instead of slowing down gradually. This creates more friction and heat, reducing pad lifespan.

https://www.bimmer-mag.com/car-disc-brakes-wearing-out/

Re: Dust from car brakes more harmful than exhaust, study finds

#244

Post by rightbyte »

lukevp wrote: post #215
kstrauser wrote: post #207

Earlier quoted context omitted.

Not significantly. Otherwise they’d get hot and work less well. Pads ride very closely to the disc so that road stuff can’t get wedged between the surfaces, and so that you don’t waste break pedal travel just getting the pads close to the surface. Well adjusted drum brakes should be arranged almost exactly the same way. From https://mechanicswizard.com/how-close-should-brake-pads-be-t... : > Typically, the optimal ga…

Are you familiar with how disk brakes on a car operate? They’re essentially a hydraulic piston clamping the brake pads against the rotor. When you let off the brake pedal, the pressure is removed, but there’s not a “retraction” of any kind. So there’s no pressure but nothing is actually making that gap. That article was articulating basically that the piston, when not compressing the brake pads, should not be too far…

> When you let off the brake pedal, the pressure is removed, but there’s not a “retraction” of any kind. So there’s no pressure but nothing is actually making that gap.

The wobble pushes the pads back in, right?

Re: Dust from car brakes more harmful than exhaust, study finds

#245

Post by Scoundreller »

NewJazz wrote: post #236
caycep wrote: post #212

Earlier quoted context omitted.

Granted, I would still rather them designed for lighter weight. But that’s a separate issue w suv culture which is bad for society and environment in general. Totally would buy a 3000 pound EV around the size of a euro hatch.

There are a few ways to get the weight down. Improvements in battery chemistry, lower range trims, and simply smaller vehicles.

Would love to buy a 100km range EV with easily accessible/rentable +~300km booster batteries for the occasional long drive.

I guess an occasional ICE rental could fill the gap but they often nail you on long distances

Re: Dust from car brakes more harmful than exhaust, study finds

#247

Post by hinkley »

orev wrote: post #88

The Yale article and the paper both highlight the fact that EVs use regenerative braking and produce less dust. I was worried that this was a rehash of the astroturf campaign from a few years ago focusing on EV weight and how that was so bad for the environment because of tire and road wear. Unfortunately you need to read through the whole thing (instead of the headline and a few paragraphs) to see that information.

The brakes on my VW lasted so long that I called all the shops I’d been to see if they had a record of me buying new pads. The last guy said they were aftermarket, so I don't know if there’s a shop I forgot or may have accidentally gotten new pads because someone read a work order wrong.

But they still last a long time because the DSGs of that era used engine braking and lots of gears to get better gas mileage than the manual version. Which was rare up to that point. Manual almost always got you better mileage than the automatic.

Engine braking saves you a ton because the brakes wear out faster the harder you brake. I don’t recall if it’s just the pressure or if it’s the heat.

Now he did tell me the aftermarket’s don’t have copper sinters in them, which is how he clocked them as replacements. Sometime after I bought my car they banned copper in brake pads due to metal pollution.

Re: Dust from car brakes more harmful than exhaust, study finds

#248

Post by Scoundreller »

dv_dt wrote: post #171
blackeyeblitzar wrote: post #111

Earlier quoted context omitted.

Has someone actually measured that tradeoff (weight versus regenerative braking) to determine where it is an even tradeoff? And surely regenerative braking has its own shedding of particles from all the moving parts.

Owning a hybrid with regenerative braking vs a non-hybrid of the same class of vehicle, there is a noticeable reduction in brake wear and replacement with regenerative braking.

Can confirm the same with a manual transmission'd vehicle.

About 140k miles in and I've replaced the pads+rotors once (but will replace next summer)

Re: Dust from car brakes more harmful than exhaust, study finds

#249

Post by carlosjobim »

mezzie2 wrote: post #49
amazingamazing wrote: post #27

Earlier quoted context omitted.

You show me one of these that can be ridden [comfortably] in 2 degrees Fahrenheit with snow and ice everywhere and you have my money!

Or by people who are disabled/elderly. I have MS, cycling isn't really going to work on a regular basis because between heat intolerance and cold making my leg spasticity worse, I'm not going to have a good time. I can drive just fine, though. While yes, a lot of the elderly continue to cycle in countries where the infrastructure exists (e.g. the Netherlands), those places also have universal healthcare. You can't ju…

Did he say that exactly everybody in the world has to ride a motorcycle? Of course there will be people who can't, but most people can.

Groceries can easily fit in a top box for a motorcycle, that you usually have anyway to stove helmets.

Re: Dust from car brakes more harmful than exhaust, study finds

#250

Post by Scoundreller »

caycep wrote: post #213
bobsmooth wrote: post #199

Earlier quoted context omitted.

I live on the second floor near a road and my balcony furniture is always covered in black gunk.

There was that whole study with some additive in tire compounds, killing whole rivers of salmon until they figured out what it was

EVs can be pretty bad for tire wear, not just due to vehicle weight, but the amount of torque available (and consistently available) that leaves most ICE vehicles in the dust.

Depends on driving style of course

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