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1. thefz+(OP)[view] [source] 2024-01-29 13:24:57
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.
replies(6): >>Richar+s2 >>dgacmu+w2 >>jwcacc+g3 >>infect+k3 >>D13Fd+q4 >>piva00+gc
2. Richar+s2[view] [source] 2024-01-29 13:38:47
>>thefz+(OP)
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.
replies(1): >>thefz+AR1
3. dgacmu+w2[view] [source] 2024-01-29 13:38:52
>>thefz+(OP)
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 reduces tire wear but that's possible with either mode.

replies(1): >>thefz+7T1
4. jwcacc+g3[view] [source] 2024-01-29 13:43:15
>>thefz+(OP)
What? Tires are the way cars touch the road. If you're slowing down from engine breaking or from friction breaking, the force between the tires and the road will be the same. It's not like engine breaking has some alternative connection to the road.

And that says nothing about the fact that EVs use regenerative breaking, where the motors turn that kinetic energy into electricity to charge the battery, slowing things down with the friction breaks.

5. infect+k3[view] [source] 2024-01-29 13:43:39
>>thefz+(OP)
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.
replies(1): >>stavro+l5
6. D13Fd+q4[view] [source] 2024-01-29 13:49:41
>>thefz+(OP)
Isn’t regenerative braking similar?
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7. stavro+l5[view] [source] [discussion] 2024-01-29 13:55:06
>>infect+k3
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.
replies(1): >>thefz+xS1
8. piva00+gc[view] [source] 2024-01-29 14:35:49
>>thefz+(OP)
Engine braking uses the tyres to slow down. Every motion a car does uses the tyres, no matter how it's done mechanically.

And as other comments mentioned, there's regenerative braking on EVs which, in tyres' mechanical terms, behave very similarly to engine braking.

replies(1): >>thefz+eT1
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9. thefz+AR1[view] [source] [discussion] 2024-01-29 21:41:45
>>Richar+s2
Regenerative or not, while braking you are still inflicting the whole weight of your car onto the tyre threads.
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10. thefz+xS1[view] [source] [discussion] 2024-01-29 21:47:06
>>stavro+l5
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?

replies(2): >>stavro+bT1 >>infect+ID3
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11. thefz+7T1[view] [source] [discussion] 2024-01-29 21:49:34
>>dgacmu+w2
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.

replies(1): >>dgacmu+rs3
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12. stavro+bT1[view] [source] [discussion] 2024-01-29 21:49:59
>>thefz+xS1
I don't see where you disagree. Indeed, any kind of deceleration exerts wear on the tyres. It doesn't matter if the deceleration is because of an electric motor or an ICE, the wear is the same for the same deceleration.
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13. thefz+eT1[view] [source] [discussion] 2024-01-29 21:50:14
>>piva00+gc
Absolutely not the same.
replies(1): >>piva00+S43
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14. piva00+S43[view] [source] [discussion] 2024-01-30 08:42:26
>>thefz+eT1
It's definitely very much the same from the tyres perspective, regenerative braking happens on the axle which slows the tyre rotation and the tyres friction grips pavement to slow down the mass. Engine braking is the exact same: slowing the axle through the engine, the effects on the tyres is the exact same.

Let me know what's different in your mind and we can have a conversation, you're just wrong.

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15. dgacmu+rs3[view] [source] [discussion] 2024-01-30 12:17:24
>>thefz+7T1
Engine braking does the same thing. It just applies resistance by using the engine instead of by using the brakes. Whether the slowing force is transmitted by the axle or the brakes is irrelevant to tire wear.
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16. infect+ID3[view] [source] [discussion] 2024-01-30 13:36:39
>>thefz+xS1
Then we are in agreement your original comment is wrong?

You seem pretty confused on the physics/mechanics of it. On a gas engine there is a vacuum created when you release the accelerator which requires force to continue to turn the engine via the drive shaft. The how is not whats causing you to skid its the amount of force. The force from a brake or the engine does not matter. I know there are conspiracy theorists online that suggest somehow its different but its really just the amount of force. Engine braking is a lot lower force than a hydraulic brake.

It all comes down to the friction between the tire and the road surface.

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