sgt1372
Posts: 533
Joined: Mon Feb 06, 2017 4:21 pm
Location: SF Bay Area

Re: Too much regen in D mode

Wed Aug 16, 2017 3:44 pm

redpoint5 wrote:...and you might not coast in neutral in your automatic, but I do.


Just because you do it doesn't mean it's the proper thing to do.

It is in fact unsafe and potentially dangerous. You are not just endangering yourself but also others when you do.

See: https://www.quora.com/What-are-the-dang ... in-neutral
My vehicles:

2012 Mercedes ML350 4Matic
2008 BMW 335i
2002 Toyota MR2 Spyder
2002 Ford F250 7.3L 4x4 Longbed Turbodiesel
2000 Porsche 911 Carrera 4 Cabriolet

redpoint5
Posts: 76
Joined: Tue Apr 04, 2017 5:17 am

Re: Too much regen in D mode

Wed Aug 16, 2017 4:29 pm

sgt1372 wrote:
redpoint5 wrote:...and you might not coast in neutral in your automatic, but I do.


Just because you do it doesn't mean it's the proper thing to do.

It is in fact unsafe and potentially dangerous. You are not just endangering yourself but also others when you do.

See: https://www.quora.com/What-are-the-dang ... in-neutral


No, it's not unsafe. Being distracted or inebriated is less safe. My stopping time isn't reduces at all by coasting in neutral. You're the one making the claim, so it's up to you to provide the statistics of accidents caused by nothing other than being in neutral. I'm sure there have been accidents, after all, people are struck by lightning sometimes too.

I almost went off a cliff on a snowy logging road once. The tail of the truck broke loose from the slight engine braking, and being completely off the brakes wasn't enough to regain control. In the last moment, I thought to shift to N, which allowed the rear end to hook back up, and I was just able to make the bend.

Whatever statistic you find for accidents caused by being in neutral, subtract the number of accidents caused by being in D.

sgt1372
Posts: 533
Joined: Mon Feb 06, 2017 4:21 pm
Location: SF Bay Area

Re: Too much regen in D mode

Wed Aug 16, 2017 4:39 pm

redpoint5 wrote:No, it's not unsafe. Being distracted or inebriated is less safe. My stopping time isn't reduces at all by coasting in neutral. You're the one making the claim, so it's up to you to provide the statistics of accidents caused by nothing other than being in neutral. I'm sure there have been accidents, after all, people are struck by lightning sometimes too.


"Me thinks thee protests too much."

It's not just my opinion that it's unsafe, which is why I added the link above. Did you even read it?

If you're unconvinced so be it. You're not the only person doing whatever they want to do on the road in violation of the law.

I do it too when I speed but at least I'm aware of the risks that arise when I do. Still not sure that you are aware of the risks of doing what you do.

Ciao!
My vehicles:

2012 Mercedes ML350 4Matic
2008 BMW 335i
2002 Toyota MR2 Spyder
2002 Ford F250 7.3L 4x4 Longbed Turbodiesel
2000 Porsche 911 Carrera 4 Cabriolet

redpoint5
Posts: 76
Joined: Tue Apr 04, 2017 5:17 am

Re: Too much regen in D mode

Wed Aug 16, 2017 6:24 pm

sgt1372 wrote:It's not just my opinion that it's unsafe, which is why I added the link above. Did you even read it?

If you're unconvinced so be it. You're not the only person doing whatever they want to do on the road in violation of the law.

I do it too when I speed but at least I'm aware of the risks that arise when I do. Still not sure that you are aware of the risks of doing what you do.


I read the link, but it lacked much substance. Perhaps the last comment was closest to the reality of how things work.

Nowhere have I suggested allowing a vehicle to run away in neutral. In fact, my comment about coasting has nothing directly to do with hills at all. The link only talked about grades so steep that a vehicle would gain too much speed unless slowed. It ignores the more frequent moderate hills we encounter such as overpasses.

When I encounter a steep enough hill that I need to prevent an unsafe speed, I leave my car in D, or downshift as needed. One thing not even mentioned in the ignorant posts in that link is the benefit of fuel cutoff gained by leaving a car in D. Both automatic and manual cars stop injecting fuel when the engine is slowing the vehicle, which saves fuel. Coasting in neutral in a conventional car doesn't turn the engine, so fuel has to be burned to maintain engine RPM.

I'm fully aware of the "dangers" of coasting in neutral. I don't use N when it's an inappropriate time to use it, such as controlling excessive speed, or otherwise trying to slow down. If I die because of an accident that could have been avoided had I saved the 0.3 seconds it takes me to shift back to D, and accelerate to safety, you may inherit everything I own, as long as you agree to allow me to inherit your possessions if "speed was a factor" in your death.

... and who is the one protesting here? I'm in full agreement with the OP. Anyone who disagrees is doing the protesting.

dandrewk
Posts: 239
Joined: Sat Dec 17, 2016 6:29 am

Re: Too much regen in D mode

Wed Aug 16, 2017 7:55 pm

PV1 wrote:
dandrewk wrote:The Bolt is a small car, but it is very heavy due to those batteries. It takes a lot of stopping power to slow/stop this vehicle, so having some level of regen or transmission slowing is a very good thing.

I'd hate for some Bolt driver, in a quest to increase his/her efficiency, coast downhill from the I5 Grapevine into the LA suburbs in "N", only to find that using 100% friction brakes has caused them to overheat. Ever try and use overheated brakes to slow/stop a car? Get ready to scream "WTF??!!"...

Umm, why would anyone use friction brakes while purposely shifting into Neutral in the Bolt? Drop it back into Drive/Low if you need to slow down. Using Neutral is only to shut off regen for coasting, not bypass the motor and rely on friction brakes (which would be way more wasteful than the 13 kW of regen induced in Drive mode).

Folks have done hundreds of thousands of miles in EVs and coast in Neutral. I don't think anyone's overheated brakes.


Umm, well lots of folks here are trying to justify this inherently dangerous behavior.

As to your "hundreds of thousands of miles", I'd love to see any citations regarding this. And regardless, there are also lots (not all) of folks who have driven many times that amount while under the influence of alcohol, drugs, medications etc, and have not suffered any consequences. Does that make it safe for them?

But I'm done with this off topic tangent. Drive as you wish.

sgt1372
Posts: 533
Joined: Mon Feb 06, 2017 4:21 pm
Location: SF Bay Area

Re: Too much regen in D mode

Wed Aug 16, 2017 8:29 pm

dandrewk wrote:But I'm done with this off topic tangent. Drive as you wish.


Ditto.
My vehicles:

2012 Mercedes ML350 4Matic
2008 BMW 335i
2002 Toyota MR2 Spyder
2002 Ford F250 7.3L 4x4 Longbed Turbodiesel
2000 Porsche 911 Carrera 4 Cabriolet

PV1
Posts: 38
Joined: Mon Jul 31, 2017 8:11 pm

Re: Too much regen in D mode

Wed Aug 16, 2017 8:36 pm

Then I'll leave with just this disclaimer.

If you choose to coast in Neutral, keep a hand on the shifter so you can get back into gear quickly, be aware that you need to shift before regaining motive power, and use the friction brakes when necessary (panic stops, when regen alone isn't enough, etc.).

Use common sense.
2012 i-MiEV ES with quick charge - White
2012 i-MiEV ES with quick charge - Silver
2017 Bolt EV LT - Orange Burst

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redpoint5
Posts: 76
Joined: Tue Apr 04, 2017 5:17 am

Re: Too much regen in D mode

Wed Aug 16, 2017 10:22 pm

dandrewk wrote:
PV1 wrote:
dandrewk wrote:I'd hate for some Bolt driver, in a quest to increase his/her efficiency, coast downhill from the I5 Grapevine into the LA suburbs in "N", only to find that using 100% friction brakes has caused them to overheat.

Umm, why would anyone use friction brakes while purposely shifting into Neutral in the Bolt? Drop it back into Drive/Low if you need to slow down. Using Neutral is only to shut off regen for coasting, not bypass the motor and rely on friction brakes (which would be way more wasteful than the 13 kW of regen induced in Drive mode).

Folks have done hundreds of thousands of miles in EVs and coast in Neutral. I don't think anyone's overheated brakes.


Umm, well lots of folks here are trying to justify this inherently dangerous behavior.

Not a single person has advocated dangerous driving behavior, except for one person with a hypothetical scenario of riding the brakes while coming down the grapevine, which I'm sure the Bolt can safely accomplish, even if it is hard on the brakes.

As to your "hundreds of thousands of miles", I'd love to see any citations regarding this.

But I'm done with this off topic tangent. Drive as you wish.


Every Golf EV comes with a true coast mode, and some drivers have chosen to utilize it. You're the one making the danger claim, so the onus of proof falls on you. I'd love to see some citations that it's dangerous. I'm eager to admit being wrong when shown proof of my error.

... and that's the point, not all of us can drive as we wish, because there is no coast mode.

dandrewk
Posts: 239
Joined: Sat Dec 17, 2016 6:29 am

Re: Too much regen in D mode

Thu Aug 17, 2017 12:07 am

redpoint5 wrote:
dandrewk wrote:
PV1 wrote:Umm, why would anyone use friction brakes while purposely shifting into Neutral in the Bolt? Drop it back into Drive/Low if you need to slow down. Using Neutral is only to shut off regen for coasting, not bypass the motor and rely on friction brakes (which would be way more wasteful than the 13 kW of regen induced in Drive mode).

Folks have done hundreds of thousands of miles in EVs and coast in Neutral. I don't think anyone's overheated brakes.


Umm, well lots of folks here are trying to justify this inherently dangerous behavior.

Not a single person has advocated dangerous driving behavior, except for one person with a hypothetical scenario of riding the brakes while coming down the grapevine, which I'm sure the Bolt can safely accomplish, even if it is hard on the brakes.

As to your "hundreds of thousands of miles", I'd love to see any citations regarding this.

But I'm done with this off topic tangent. Drive as you wish.


Every Golf EV comes with a true coast mode, and some drivers have chosen to utilize it. You're the one making the danger claim, so the onus of proof falls on you. I'd love to see some citations that it's dangerous. I'm eager to admit being wrong when shown proof of my error.

... and that's the point, not all of us can drive as we wish, because there is no coast mode.


Pedantic straw man arguments aside, I agree.... "there is no coast mode". Why? Because the car manufacturer knows that overheating brakes and premature brake pad wear is a dangerous situation. Did you read the manual?

Question: Are you driving an automobile... or a box car?

That was a rhetorical question, because, as I said, drive as you wish.

SeanNelson
Posts: 1462
Joined: Tue Jul 05, 2016 2:43 am
Location: Vancouver, BC

Re: Too much regen in D mode

Thu Aug 17, 2017 2:48 am

dandrewk wrote:Pedantic straw man arguments aside, I agree.... "there is no coast mode". Why? Because the car manufacturer knows that overheating brakes and premature brake pad wear is a dangerous situation.

Ridiculous!!!!

If there really was a "coast mode", all it would do is to neither apply power nor regen when you lift your foot completely off the accelerator. That's it. It would have the same effect on driving the vehicle in "normal" ("D") mode as if you pressed the accelerator just enough to eliminate the slight regen you get in that mode.

"Coast mode" would not disable regen when you use the brake pedal or the regen paddle. Both of those would operate exactly the same. So there would be no brake overheating issue at all. We are not talking about using "N" to coast, we're talking about a user-selectable option of some sort to disable the slight regen you get in "D" mode when you lift your foot completely off the pedal.

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