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Comment by brtkwr | Hacker News Reader

Just normal driving, it wasn’t quite so bad on our previous car which was a Nissan Leaf (with 30kWh battery) but our current Kia Niro just has a lot bigger batter (64kWh) and it is a lot heavier I suppose, the tyres just don’t seem to last as long. I’m pretty sure I’m using summer tyres all year round (I live in the UK) this was recommended by the dealer

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Some tyre compounds wear a lot faster than others (though often with better grip). I wonder if that's contributing.

The other thing is poor alignment (especially toe settings) which cause the tyres to fight each other constantly. It can be a very small difference, almost imperceptible but still accelerate the wear.

10k miles is very short for a tyre.

Often you can tell a lot from the tyre temperature after a drive: if they're getting very warm, it can indicate problems, e.g. if one axle has much warmer tyres than the other (hard to give an objective standard on that, though, so many factors)

Aren’t higher speed rated tires softer? Maybe try swapping for a lower speed rating unless they plan on driving it at extreme speeds.

I heard Kia Niro has the front wheel drive issue and the tires wear on the front very fast. So you should swap front wheels and rear wheels every year to get best wear result. I drive very poorly and fast, but usually mid-range tires last for at least 30k miles on different cars.

This is known as rotating tires, and is a good idea to do periodically for other reasons as well.

Either you're lying about your driving habits, or there's something wrong with your car.

I've got a Model 3 Performance which came with the Michelin Pilot Sport 4 tires which are only warrantied for 30,000 miles. I had them for 5 years and 35,000 miles and they STILL had plenty of tread left. I had to replace them anyways because I hit a nasty pothole that caused the tread to separate.

Are you driving fast(er than with a ICE vehicle) in corners? Since EVs have a very low center of mass, drivers tend to take corners a lot faster than they would in ICE vehicles which is very hard on the tires.

A friend got hit by this as well and since readjusting his driving style (read: not flying through corners for the fun of it) he gets more (but still not equal) miles on his EV's tires before he needs new ones.

I have the Hyundai Kona, which I'm pretty sure is just their version of the Nero (same 64kWh battery at least). I'm on my original tires after 44k miles.

I also have a Kona and I had to replace mine at around 30k.

My numbers are probably better than average since, living in a rural area, a lot of my driving is either freeway or long stretches of rural road without many stops, so I do less accelerating/decelerating/turning corners than someone driving in a city, which, as many people point out in this thread, is where most of the wear happens. Your experience is probably more typical than mine is, but even yours is a heck of a lot different than every 10k miles.

The additional battery weight would be something under 250kg (having handled a few Leaf battery packs), and wikipedia says the Niro EV is about 1700kg

I'm sorry but I've got two EVs and I'm not seeing anything like what you're reporting. On my first set of tires for a model S I got 60k miles which is longer than I usually like to run tires but they were still in good shape. My driving pattern is about 80% grandpa-mode and 20% speeding to loud music.

I assure you. If your EV tires are only lasting 10K miles you have one of the following cases:

- You are driving VERY aggressively

- Your car has an alignment issue or some sort of torque vectoring problem

- Your tires are absolute shit

He (like me) is in the UK - unless you go for a brand name, many of the tyres people run here are low quality import tyres - while 10k is low, my ICE has occasionally only got 20k from a set, but that is mainly due to the tyres cracking from sun damage (still got over 4 year out of them before that happened).

Cheap tyres are often a bad investment, but I drive country lanes with a higher risk of punctures and I was burning through brand name tyres, a full set is worth more than my car!

Mine lasted 11k km before I was seeing interleave.

Alignment is fine, had it checked when I had a new set of continentals fitted.

My problem is purely that I drive like an asshole, on very windy, empty roads. Every day is track day.

Decent tyres, too, continentals - soft compound, hard roads. Means it corners like a dream right up until the tyres are bald.

Perhaps do an advanced driving class? Assuming no mechanical issues the next place to look is your driving. 10k is way too low, something is not right.

10k per set of tires seems like a high "smiles per gallon" number to me.

Some EVs have low rolling resistance tires to increase the range. I think they will wear out faster, especially if cornering sharply.

The factory fitment LEAF tires seem to be made of cast iron, based on the unimpressive levels of cornering grip but also on their impressive long-wearing nature.

I'm likely to end up replacing mine based on age-related degradation rather than wear.

I too am UK based, but I have a Zoe, which is not as heavy as the NEO.

But my inlaw has a neo from new and hasn't replaced the tyres yet, and hes an auto obsessive. He lives in the midlands and drives 18k a year.

remember, your regenerative braking comes at cost of tire life.

If driving Tesla, you can reduce the regenerative breaking from Maximum setting to Medium.

this will reduce regeneration and will increase the "breaking distance" when you just let go of accelerator pedal.

but it will increase your tire life significantly.

also make sure to buy the "commuter tire" models - tires with high mileage warranty (50k miles+) and harder compound. Even if it wears out faster, tire manufacturer's warranty will make up for it by giving you discount for the replacement tire purchase

Huh? What do you imagine is the tradeoff between regenerative braking and tire life? Are you suggesting that stopping the car with conventional iron brakes is somehow easier on the tires?

the level of regenerative braking directly impacts your accelerator pedal behavior.

by reducing regeneration, you will increase tire life by virtue of modifying your acceleration behavior. Its hard for me to explain, but I just suggest trying the medium regenerative setting and you will see it yourself.

You will feel it, because the most of the tire wear happens when car decelerates. On less regeneration your car will decelerate less and will wear out tires slower

That's a whole lot of assumptions based on what?

I could come up with a list of plausible sounding reasons why regenerative braking leads to less tire wear. Unless you have some actual measurements, I wouldn't trust either one.

I'm reading it as referring to a setting where the car will brake some amount (instead of coasting) if you completely let go of the pedals, and as being a claim that the commenter can't maintain speed but gets stuck in a cycle of accelerating and then letting the car brake.

I've never driven an EV, only a hybrid a few times, but I thought for all cars with aggressive regenerative brake settings, you just kept the accelerator pedal slightly depressed to coast.

I use one peddle driving all the time and manage to keep a steady speed as I'm doing it. Why would you be constantly taking your foot off the accelerator unless you need to slow down?

I'll also throw another anecdote in for this thread, 500hp EV, 50k miles on the tyres.

most of the tire wear happens when car decelerates

Is this generally true? I imagine it depends on the car/driver to a certain extent, but still I'd be curious what numbers are out there.

when car decelerates, the kinetic energy has to go somewhere, large part of it goes to battery as regeneration (60%), the rest goes to tire/road friction and wear

That doesn't answer my question even a little bit.

From the physics perspective, where does kinetic energy go in E=1/2mv^2 ?

Up to 60% goes back to battery, part goes to air resistance and rolling tire resistance (can be ignored for our case as its the same regardless of regen setting), the rest goes to friction of tire/road due to slowing down tire speed

Your claim was that most of the tire wear for cars was due to deceleration. Acceleration could be to blame too. I asked for a source for your claim, not math equations.

No one is debating that deceleration results in tire wear.

The two claims you've made are that deceleration results in more tire wear than acceleration, and that regenerative deceleration results in more tire wear than non-regenerative deceleration. These are what people are questioning you about.

acceleration is irrelevant because you need to accelerate to move regardless.

what is relevant to prolong the tire lifetime is reducing the unnecessary tire friction against the road.

There is constant component that depends on the weight * velocity * mileage - you gonna encounter it in all scenarios

There is also a variable component that is driven by 1st derivative of speed (rate of acceleration/deceleration).

The high regeneration allows you faster acceleration/deceleration, but medium/lower will (1) change your driving behavior so that you accelerate more smoothly, and (2) change your deceleration so that you coast more and decelerate less

remember, car's kinetic energy is not a perfect energy storage, so that you could freely move energy from battery into car speed, and regenerate it back into battery.

apart from air resistance, there is 60% loss on the way back + tire wear penalty depending on accel/decel curve (1st speed derivative)

remember, your regenerative braking comes at cost of tire life.

No, it doesn’t. The tires don’t care if it’s the car’s motor slowing things down, or some friction material grabbing a disc.

I guess they are saying that the sharper braking curve that is default on Teslas is going to cause more wear than a slower braking curve. The logic makes sense, but I have some doubt's that sharp regen breaking is more to blame for tire wear vs. Sharp manual braking and acceleration.

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