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New tires every 7k miles? Electric cars save gas; tire wear shocks some drivers

miamiherald.com

51–60 of 66 posts

Re: New tires every 7k miles? Electric cars save gas; tire wear shocks some drivers

#51

Looks like an astroturf campaign, with essentially the same story popping up around the country. https://news.ycombinator.com/item?id=39159783

Based on the quotes near the end of the article I’d guess it was a tire retailer’s PR department. Either that or the oil lobby, naturally

Re: New tires every 7k miles? Electric cars save gas; tire wear shocks some drivers

#52
I'd love to see a real analysis instead of anecdotes, and particularly one that separates Tesla vs. others. My Tesla owning friends all complain about this; none of my Nissan/Ford/VW owning friends do. I suspect that BMW/Mercedes/Porsche EVs tend more toward the Tesla end, because it's mostly about acceleration and people with lead feet, but I'd like to see some hard evidence.

Re: New tires every 7k miles? Electric cars save gas; tire wear shocks some drivers

#53
post #45

Earlier quoted context omitted.

A Tesla Model 3 is 0-15% heavier than a BMW 3 Series. A Ford Lightning is 10-20% heavier than a gasoline SuperCrew. EV's are not 40% heavier.

Glad to see at least one other person agreeing, I got the doom and gloomer downvotes.

I think it may simply be a US vs European thing, it really surprises me the modern ICE cars are so heavy. I guess it's because of SUVization.

Re: New tires every 7k miles? Electric cars save gas; tire wear shocks some drivers

#55
post #6

Looks like an astroturf campaign, with essentially the same story popping up around the country. https://news.ycombinator.com/item?id=39159783

I would not be surprised if tires wear faster on a vehicle that weighs ~40% more. Another thing to consider is road damage, which is famously proportional to the weight to the power of four. [1] [1] https://en.wikipedia.org/wiki/Fourth_power_law

Where did you get 40%? The EV version of my car (Ford Focus) is 10-20% more than a typical Ford Focus (depending on trim).

Re: New tires every 7k miles? Electric cars save gas; tire wear shocks some drivers

#56
post #29
post #22

Earlier quoted context omitted.

No, EVs do not damage roads. Its not famously proportional, there is a cut off and consumer vehicles, including EVs, do not damage roadways. Large semi trucks do. Not sure how you calculate 40% but that sounds wildly off, unless you are cherry picking and comparing a Rav 4 to that wildly heavy Hummer. Lets take a real comparison though, Model Y at the top end is 4400lbs, a Rav4 at the top end is 3600lbs. Thats a 22%…

The car I drive weighs about 1300 kg, the Tesla Model X is about 2400 kg. I was being conservative with 40%. Edit: turns out my car weighs even less. Edit2: asked Google for most common, seems Tesla Model S at around 2100 kg.

When you cherrypick your comparison options, you can come up with some crazy statistics. What vehicle do you drive, and would you honestly compare it with a Model X (a large SUV)?

Re: New tires every 7k miles? Electric cars save gas; tire wear shocks some drivers

#58
post #34

Earlier quoted context omitted.

You can't engine-brake with an electric engine (with a combustion car, downshifting will force your car to be slower when going downhill, basically) so in mountain regions with ups and downs there's way more braking leading to massively increased tyre wear.

You clearly haven’t owned or driven one. Most have a configurable setting for regenerative braking, where the rotation of the wheels turns the motors to put energy back into the battery, and this has a very similar effect on speed. Less flexible, perhaps, than engine braking, as most EVs have a single forward gear, but I’ve now driven 86,000 miles in mine and am still on the factory discs and pads.

Regenerative or not, while braking you are still inflicting the whole weight of your car onto the tyre threads.

Re: New tires every 7k miles? Electric cars save gas; tire wear shocks some drivers

#59
post #46
post #43

Earlier quoted context omitted.

Can you please explain the mechanics of this? Engine braking, ignoring a semi jake brake style, is using the weight of the engine to slow the vehicle down. The mechanics of an EV using regen in my head seems pretty similar. You are generating electricity which is creating resistance, similar to how turning the engine without using petrol is creating resistance.

There's no difference in mechanics, the resistance on the wheel's axle is similar, therefore tire wear is similar. The GP doesn't seem very informed.

You don't seem very informed to me. Any kind of deceleration will exert some wear on the tyres.

While engine braking it is not about the weight of the engine used to slow the vehicle down, but rather forcing the wheels directly connected to the engine to a fixed speed. When you clamp your brake, you are trusting the tyre's stickiness to slow the car down, pushing them into an abrasive surface, ultimately wearing them down.

Ever wondered why on a slippery surface the engine brake works while braking don't?

Re: New tires every 7k miles? Electric cars save gas; tire wear shocks some drivers

#60
post #41
post #34

Earlier quoted context omitted.

You can't engine-brake with an electric engine (with a combustion car, downshifting will force your car to be slower when going downhill, basically) so in mountain regions with ups and downs there's way more braking leading to massively increased tyre wear.

First, you can: many electrics have a regenerative braking mode that you can engage that will provide some amount of "engine braking"-equivalent slowing down. And on some of them you can select how much slowing is applied. It's very similar to manually selecting a gear. Second, huh? How does engine braking reduce tire wear at the same speeds? Brakes do not contact the tire. It reduces brake wear... Gentle braking red…

Absolutely not the same thing.

> Brakes do not contact the tire. It reduces brake wear...

When braking you are basically limiting the tyre's rotation leveraging the tyre's stickiness to slow you down, and ultimately wearing it down. This is why where there is no abrasive surface under your car, i.e. snow, stopping down is harder. Or just accelerate to 100Kmh and then stomp on your brakes, then notice how they are all worn out where they contact the ground.

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