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Comment by slau | Hacker News Reader

Do you know where the increased tyre wear comes from? I run a PHEV, and if anything, my tyre wear has improved.

This being said, I’ve noticed that many a “big EV” driver will take off from red lights like they’re driving a dragster.

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> This being said, I’ve noticed that many a “big EV” driver will take off from red lights like they’re driving a dragster.

That would be my guess. Occasionally looking at specs from EV's coming on market, they seem to have very powerful engines, and of course the torque curve of electric motors is fantastic. So if you have such a car, and a heavy foot, I can well imagine you going through tires at a decent clip.

All else equal, the higher rate of BEV tire wear is primarily a function of their greater weight relative to comparable vehicles.

>>All else equal

That's equivalent to those high school physics exercises that say "assume zero friction and no gravity". Everything else isn't equal with EVs because they make accelerating from standstill so effortless without any obvious downside that people do it back to back like it's nothing, while in an ICE you'd have to drive like a madman dumping the clutch every time just to get the same torque at the start. If you had two cars accelerating at the same rate then sure, the heavier one would wear out its tyres faster - but that's just not how people drive EVs(broadly speaking).

There are EVs that aren't overpowered luxury cars. They also burn through tires faster.

Also, if you compare two gasoline cars of different weights, the heavier one burns through tires quicker.

That's exactly what I'm saying though. I have an EV that's only 1000kg and 80bhp and it goes through tyres like butter.

Extra weight because of the battery, I think. Our EV is light for its size, but still 50% heavier than our previous ICE, of a similar size (Renault Scenic e-tech, 1.8 tonnes vs SEAT Leon ST, 1.2 tonnes).

Though the additional acceleration probably does also make a difference.

I think most reasonable explanation is likely very much increased torque and rather poor traction control leading to common slipping. Which directly wears tires.

Hybrid vehicles generally have less torque so they have less this type of wear. Unless driven purposefully aggressively.

Clear solution would be to limit acceleration of vehicles and mandate traction control that limits this type of wear.

I'm surprised EVs don't all have traction control since there's already got to be a computerized control loop for motor drive at that power level. And slipping is an obvious problem when max torque is at zero RPM.

One reason could be to get those low 0-100 rates. When actually from 0 to low speed part of that really isn't important in most scenarios. 60 or 80 to 100 sure. But 0 to 20 not so much.

Increased tire wear comes from the weight of the car and cornering. The tires need to do significantly more work in accelerating (the centrifugal kind) a car around corners at equal speed.

So obviously and logically speaking, an ICE car of equivalent weight should have the same tyre wear, and we know that's not true - there are some very heavy ICEs around which still manage to do 50k miles on a single set of tyres without any issue. EVs have instant torque from 0rpm and people use it and that's the main reason.

Case in point - we have a Volkswagen e-Up, it barely weighs 1000kg, it's pretty much one of the lightest cars on the road. And yet it goes through its front tyres like nothing, and that's despite very modest power output of only 80bhp. But I do accelerate hard as it's so easy to do - so it's reflected in the tyre wear.

I agree there are effects of increased linear acceleration, however I disagree with you because of:

On many roads you accelerate and brake less often than you go around corners.

These two things are equivalent on tire wear given the forces involved:

1 corner at 50kmh with 50m radius.

Accelerating linearly at 0.39g (7 second 0-100kmh) to 77kmh from 0.

I don't think that's neccessarily a disagreement? Both things can be true - if you mostly drive on roads with fast corners, the heavier car will wear out its tyres faster. If you drive on roads with lots of start/stop traffic but not many "at speed" corners then the one that consistently accelerates harder will wear out its tyres quicker.

Yes, it depends on how you drive and where, however I would note the above: 50kmh is typical of city driving and 50m isn't exactly a tight radius. 77kmh is actually quite fast, and 0.39g is actually quite high acceleration (this is flooring it in chill mode in a Tesla model y). I am trying to say that the driving circumstances where the linear forces are more important than the horizontal forces are fewer in number.

I mean, I brake and then accelerate every time I go around corners.

I wonder if the uneven torque from ICEs somehow decreases tire wear. Or if like vibrations shake sand loose in starts or something.

That should be easy to fix though with a bit of software.

It'll be the extra weight and greater torque.

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