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Comment by Schiendelman | Hacker News Reader

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 dust per unit mass of the vehicle than they were a few years ago.

Plus, some manufacturers are now working to reduce the toxicity of their formulas. This will eliminate the issues a lot more.

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

That’s nothing compared to an i3: I don’t even get 10K miles per set. Some people report getting as many as 12K with conservative driving.

Part of the problem is the instant torque, but the narrow geometry is a bigger issue. Also, they did something to the formulation that achieves less rolling resistance for increased wear.

I also don’t think the weight is the main issue. The i3 is a bit under 3000 lbs. That’s the same as a Volvo station wagon, and they didn’t have this problem. (If I remember right, you could get 50K mile Michelins for them.)

This probably depends quite a bit on your acceleration/braking settings.

My model 3 is 5 years old and I'm still on my original set of tires (though in recent years I do put on winter tires for a few months a year). I don't usually drive like crazy (and it's an SR+ which is the least powerful model).

True, and you can do engine breaking and do milder acceleration curves in ICE car and that will significantly reduce the pad/tire wear. But if you drive like, I would speculate, most people do, Tesla will go through tires like a track car (half joking)

Sure, but the same can be said for a performance ICE car.

Agreed, the only thing I would say here is that electrics kind of give you this torque/weight combo for an every day car so I would guess in the real world electric cars end up being worse on dust production. Hopefully tires can get optimized for this as well.

I could be wrong and be using outdated information, but aren't Tesla's stock tires also low rolling resistance tires? Which does mean less road friction and less wear, but also means lower maximum traction which is a tradeoff most anybody could make if they wanted.

I think the stock Michelin Primacy MXM4 are a low rolling resistance tire.

As a Tesla owner, I'm 33k in on a set of all seasons and still in the green on two. You can't move the goalposts like that - the same is true on an ICE sports car.

Tesla model 3 and is lighter than bmw 3, but not as light as bare-ass corolla. They do eat tyres because they are fun to drive, not because of weight.

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.

That seems plausible to me. Tires are made from rubber. If friction forces exceed how strong the rubber particles stick to each other, they get pulled loose. And road surfaces aren’t perfectly smooth, so when you’re accelerating, some rubber particles will experience more force than others.

It seems believable that hard braking, even without leaving skid marks, could pull more rubber off a tire than gradual braking.

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/

The claim was tire wear, not brake wear.

Weight shift is a good reason, rear and all wheel drive Regen should result in 2+x as much contact patch, versus friction brakes typically favor the front 70/30, applying 70% of braking to only 2 tires.

The same exact reason that accelerating quickly causes far more tire wear than accelerating slowly, only in reverse. By applying more torque to brake/accelerate, you cause more lateral force on the tires (think, smearing the rubber itself) which is what causes tire wear. With more force the rubber is stretched further, which fatigues it and breaks off pieces of it over time.

> Absent any evidence, I don't believe that claim

Acceleration and deceleration is calculated the same way: m/s^2. If you decelerate faster you put more stress on the system in a non-linear way - the square of it actually. This is why sport and race cars have huge brakes. The tire friction will also augment non-linearly - it will hold a certain acceleration and then quickly give up (slipping point), but the energy has to be transferred and partly absorbed all the time.

> they weigh more and thus increase tire wear in all conditions

Then get a lighter one if that is your concern. Defaulting to ICE is the wrong idea because they have much more externalities (like one ton of fuel per year that needs actually around 1.5 if you include the extraction and transport).

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