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Dust from car brakes more harmful than exhaust, study finds

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

#181

Post by m463 »

Fronzie wrote: post #170
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.

There are EV's which have drum-brakes. That's only possible because the regenerative braking takes most of the load. Also, there are stories of brake-discs rusting out on EV's. Both point to less (friction)-brake use on an EV compared to an ICE.

I suspect drum brakes were chosen by the electron pinching EV engineers. They're the only brakes that are friction-free when not applied. Disc brakes rub (and slow the car) even when not applied.

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

#182

Post by marzell »

uxp100 wrote: post #168
prododev wrote: post #54

Earlier quoted context omitted.

Can you share them? Because physics says that damage to roads scales quadratically with weight. Not sure why tires would not experience a similar increase. At the very least, these tires are subject to higher forces due to the heavier weights of EVs. Intuitively, consistently applying higher friction forces to an object would cause higher wear.

The weights aren’t really that much higher than ICE cars, but I don’t think anyone who has owned an EV would say they don’t go through tires faster. They do. How much due to weight, how much due to better acceleration, I don’t know, but they definitely are harder on tires.

Some factors I think are involved, but I don't see mentioned - EVs produce more readily available torque in general, and also tire choice heavily factors in EV range (low rolling resistance), which has a negative impact on tread life

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

#183

Post by snozolli »

Schiendelman wrote: post #172
snozolli wrote: post #159

Earlier quoted context omitted.

surely regenerative braking has its own shedding of particles from all the moving parts. It adds tire wear, but no more than traditional friction braking. I can't see how there would be any measurable wear from any other moving parts, since it's just using a magnetic field for resistance. There are moving parts that touch, but modern, sealed bearings last a ridiculously long time.

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 tire wear in all conditions.

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

#184

Post by ndsipa_pomu »

seanmcdirmid wrote: post #148
ndsipa_pomu wrote: post #135

Earlier quoted context omitted.

I'm surprised there isn't more info available to compare vehicles/tyre wear. There's plenty of real-world driving going on, so you'd think someone would have measured tyre replacement frequencies.

Tires and driving styles vary a lot, so it would be really hard to come up with some aggregate numbers. Maybe you could compare the same very popular tire on different cars that still have enough data points to average out differing factors?

I reckon that the different driving styles could be partially dealt with by considering different classes of car. E G. Fast "prestige" cars will tend to share certain driving styles and be quite different to cheaper run-arounds.

Ideally, it'd be great if insurance companies made a big push to get some kind of standardised "black box" that drivers could fit. As well as providing extra stats, I think they'd be great for detecting illnesses. A simple driving ability stat could be produced from the typical acceleration/braking timings - smoother is better as it shows good anticipation by the driver. If their stat starts decreasing more than expected due to aging etc. then the driver could be alerted that they should consult a doctor as it could cognitive decline, eye problems etc.

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

#185

Post by tim333 »

light_hue_1 wrote: post #96
ndsipa_pomu wrote: post #60

Earlier quoted context omitted.

Also in the UK and I certainly subscribe to r/fuckcars as I'm a keen cyclist and never got around to learning to drive. I find it annoying that media outlets (BBC - I'm looking mainly at you!) will refer to EVs as being car-shaped and then, as you said, demonise e-bikes by lumping them in with the illegal e-motorbikes (see the recent Panorama program for a clear case of not making clear the distinction between e-moto…

I cycled for like 30 years before we had kids and needed a car. The ebikes that the post refers to are a menace and should be banned. Both as a cyclist and a driver. I've almost been plowed over by some idiot sitting on what should be a motorcycle but riding on the bike path. And I've almost had my kids run over. Also, as a driver you just don't expect someone to be going so crazy fast in the bike lane. I've had peop…

You've got to distinguish the legal ebikes limited to 15mph from the illegal ones. Sure the illegal ones should be illegal and sometimes the police do actually pull them over and then the bike is usually crushed.

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

#186

Post by dijit »

AnthonyMouse wrote: post #176
dijit wrote: post #158

Earlier quoted context omitted.

I’d appreciate it if there was an attempt to actually engage here, this is hardly the gotcha you might think. Most fatalities of motorcycles are due to collisions with cars, not other bikes nor pedestrians. Diligence won’t save you if a driver unexpectedly swerves into you. Undoubtedly there are stupid people and people who are more likely to take more risks will be more likely to engage in motorcycle riding; creatin…

> Diligence won’t save you if a driver unexpectedly swerves into you. That's the point. Diligence won't save you but crumple zones might have. It's also not obvious that most collisions being with cars isn't just because most other vehicles are cars. If two motorcycles collide with each other at high speed, the damage they do to each other isn't your problem, it's the resulting loss of control and the damage to your…

My point is cars don’t necessarily deserve the deference society affords them, they’re utility vehicles, needed by fewer people than we think (but still needed). The paths we reserve for car use should be diminished.

If every person was driving an articulated truck then there would be more deaths, caused not just by collisions and poor driving but by emissions too. We’d need bigger roads too- its unnecessary for everyone to do this.

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

#187

Post by bfgeek »

chongli wrote: post #151
bfgeek wrote: post #99

Earlier quoted context omitted.

> I think as a starting point, I would expect that tire wear should remain roughly in proportion to road wear IMO this would be a suspect assumption to make w/o data to back it up. You've got two dissimilar materials interacting (in very different modes). E.g. rolling a metal ball bearing on a wood surface would obviously cause the wood to degrade far more than the ball bearing, (and even a wooden ball rolling on a w…

You quoted me out of context by cutting off a very important qualification to my statement: given the same tires on each vehicle I don’t endorse the broader statement which would imply the same wear regardless of tire material. That claim is clearly false.

The point I was after to make is that you can't assume that road wear scales the same way as tyre wear (I was assuming same material fwiw, just different loads). They are being worn under very different modes/scenarios.

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

#188

Post by hansvm »

AnthonyMouse wrote: post #162
hansvm wrote: post #103

Earlier quoted context omitted.

Maybe, but the average Tesla tire lasts half as long as my tires typically do, and the extra weight from the battery combined with the high onset torque are likely culprits (the former of which you can't fix with current battery technology when comparing otherwise apples-to-apples ICEs vs EVs if the EVs have non-negligible range, and the latter of which would require artificial limiting on the electric motor (which c…

The weight difference between a Model 3 and the average new car sold in the US is a negative number. The Model 3 is slightly lighter than the average new car. So the difference comes entirely from torque. But you could just... not have such a heavy foot.

The difference also comes from the grippier tires on the Model 3, the total tread volume on those tires compared to a smaller car, and that the Model 3 compared to the average car isn't apples to apples if you're looking at tire wear for ICE vs EV (to be fair, my car's too light to be apples to apples either, but if you look at comparably sized cars the Model 3 is heavier).

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

#189

Post by tim333 »

lazide wrote: post #115
dijit wrote: post #106

Earlier quoted context omitted.

I find it hard to take the debate seriously because the default stance of everyone against electric 2-wheelers is not manual bikes, its cars. And, cars are multiple orders of magnitude more dangerous than anything on 2-wheels. I’m sure you’re right that theres room for improvement, but instead of building infrastructure (we literally shaped cities for cars after all)- we would rather ensure that cars are incumbent fo…

Cars are far less dangerous for occupants than 2 wheeled vehicles.

There's some data that for middle aged blokes bicycles are safter if you take obesity and heart attacks into the equation.

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

#190

Post by rafaelmn »

Schiendelman wrote: post #172
snozolli wrote: post #159

Earlier quoted context omitted.

surely regenerative braking has its own shedding of particles from all the moving parts. It adds tire wear, but no more than traditional friction braking. I can't see how there would be any measurable wear from any other moving parts, since it's just using a magnetic field for resistance. There are moving parts that touch, but modern, sealed bearings last a ridiculously long time.

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…

Teslas eat tires for breakfast. Instant torque and high weight - any benefit you get from regen breaking is not scratching that.
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