Too much regen in D mode

[sgt1372]

...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-dangers-of-coasting-downhill-in-neutral

 

[redpoint5]

...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-dangers-of-coasting-downhill-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]

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!

 

[redpoint5]

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]

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]

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

Ditto.

 

[PV1]

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.

 

[redpoint5]

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]

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]

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.

 

[JoeS]

...We are not talking about using "N" to coast, we're talking about a user-selectable option

(my emphasis) of some sort to disable the slight regen you get in "D" mode when you lift your foot completely off the pedal.

EXACTLY :!:
Chevy (and all other manufacturers), are you listening?
Incidentally, count me in for having driven a couple of hundred thousand miles (in two Gen1 Honda Insights and three Mitsu i-MiEVs) spending perhaps 20% of that mileage coasting in Neutral. Just google hypermiling and FAS (forced autostop) in the Insight. Oh, and include fifty years and a half-million miles in my 1967 Saab 96V4 with freewheel - coasts every time I let up on the accelerator. "Dangerous" is a bogus argument!

 

[GetOffYourGas]

I thought this article was applicable to this thread:

http://insideevs.com/2017-chevrolet-bolt-ev-review/

What really makes the Bolt’s regen implementation special is that it can adjust to what the driver wants. You can select drive or low; you can use the regen paddle or not – there’s a level of regen for everyone. GM nailed it. There isn’t another regenerative braking system on the market that is this good. Period.

A few of the commenters point out that coasting (zero regen) is unavailable. Without that option, it's a bit disingenuous to claim that "there's a level of regen for everyone".

 

[ghn]

I have read this discussion with some interest as I have a great deal of experience coasting with the vehicle out of gear. I drove a 2002 Honda Civic manual transmission for 300,000 miles (100 miles per day) coaxing 43mpg out of it by popping it out of gear any time that I slowed down. I can assure you that there is nothing dangerous about doing this. I did replace my front pads and rotors several times but the clutch still had a lot of meat on it when I finally traded the car in. The brakes are designed to stop the car and will do so in an emergency. I am very careful driver and I always gauged the situation carefully before popping the car out of gear and I never had any sort of safety problem crop up from coasting. The need to accelerate suddenly while coasting to a stop at a light is so unlikely it is nearly non-existent.

Driving my Bolt I do not do this as I would rather get all of the re-gen that I can and I am too lazy to fool around that way. I can see where it could work to improve efficiency though.

 

[dandrewk]

I have read this discussion with some interest as I have a great deal of experience coasting with the vehicle out of gear. I drove a 2002 Honda Civic manual transmission for 300,000 miles (100 miles per day) coaxing 43mpg out of it by popping it out of gear any time that I slowed down. I can assure you that there is nothing dangerous about doing this. I did replace my front pads and rotors several times but the clutch still had a lot of meat on it when I finally traded the car in. The brakes are designed to stop the car and will do so in an emergency. I am very careful driver and I always gauged the situation carefully before popping the car out of gear and I never had any sort of safety problem crop up from coasting. The need to accelerate suddenly while coasting to a stop at a light is so unlikely it is nearly non-existent.

Driving my Bolt I do not do this as I would rather get all of the re-gen that I can and I am too lazy to fool around that way. I can see where it could work to improve efficiency though.

Here we go again. "I did this, never had an issue, so it must be safe". Wrong.

Driving in "N" is inherently dangerous. Note I am saying "N" and not the fabled "coast mode" that some here are advocating. A simple google search "driving in neutral gear" led to total admonishment against driving this way.

One example, where the author proves that driving in "N" like you did with your Civic is not only dangerous, it doesn't save any gas:

I've said, on the record, many times, that it's a bad idea to coast downhill or up to a stop sign in neutral. It's unsafe. You need to be able to use the accelerator to avoid an unexpected road hazard; cars don't handle well in neutral during sharp cornering maneuvers when the engine isn't connected to the drivetrain.

http://www.popularmechanics.com/cars/hybrid-electric/a5977/coasting-in-neutral-fuel-economy/

As I've said several times here, drive as you wish or at your own risk.

P.S. I'm not saying you are an unsafe driver, so please don't take it that way. The subject of using neutral gear to save gas/power has been around for decades. It's potentially a very bad idea.

 

[redpoint5]

Here we go again. "I did this, never had an issue, so it must be safe". Wrong.

Driving in "N" is inherently dangerous. Note I am saying "N" and not the fabled "coast mode" that some here are advocating. A simple google search "driving in neutral gear" led to total admonishment against driving this way...

As I've said several times here, drive as you wish or at your own risk.

A Google search doesn't show total admonishment because there are plenty of results that turn up saying it's fine. What you have failed to do is provide even a single case where an accident was caused by neutral.

... and you aren't advocating that people drive as they wish, as you have attempted to convince people of the extreme hazard of being in a neutral state.

Driving bumper to bumper is orders of magnitude more dangerous than leaving a gap and employing a coast, whether it be in N, or part of the vehicle design. I'm trying to remember the last time news told me "the officer on scene to the horrific accident said that neutral was a factor in the crash".

If we really want to get serious about public health and safety, then this whole conversation should be about cardiovascular disease, obesity, and cancer. Instead, this thread is about efficiency and driver choice.

If people want to continue the extremely off-topic conversation of being anti-choice, I suggest they start another thread.

 

[ghn]

One example, where the author proves that driving in "N" like you did with your Civic is not only dangerous, it doesn't save any gas:

Well, I was driving a manual so I was not really driving in "N" and it does save a lot of gas because I was not using gas to overcome the friction of the engine, this is very simple physics. I saved a great deal of gas doing this! You should go out and drive a manual transmission car and try it before passing judgement!

 

[dandrewk]

Here we go again. "I did this, never had an issue, so it must be safe". Wrong.

Driving in "N" is inherently dangerous. Note I am saying "N" and not the fabled "coast mode" that some here are advocating. A simple google search "driving in neutral gear" led to total admonishment against driving this way...

As I've said several times here, drive as you wish or at your own risk.

A Google search doesn't show total admonishment because there are plenty of results that turn up saying it's fine. What you have failed to do is provide even a single case where an accident was caused by neutral.

... and you aren't advocating that people drive as they wish, as you have attempted to convince people of the extreme hazard of being in a neutral state.

Driving bumper to bumper is orders of magnitude more dangerous than leaving a gap and employing a coast, whether it be in N, or part of the vehicle design. I'm trying to remember the last time news told me "the officer on scene to the horrific accident said that neutral was a factor in the crash".

If we really want to get serious about public health and safety, then this whole conversation should be about cardiovascular disease, obesity, and cancer. Instead, this thread is about efficiency and driver choice.

If people want to continue the extremely off-topic conversation of being anti-choice, I suggest they start another thread.

Show me where a respected source (e.g. Popular Mechanics) where it says driving in "N" is perfectly safe. Yeah, there are plenty of Joe Internet's chiming in with their own opinions, just like as in this thread. And, once again, the Bolt manual advises against driving in neutral for safety reasons.

As to your other assertions, what does that have to do with this thread? Cancer? Really?

"Driving as you wish" is my way of surrendering to the straw man posturing present in this thread. So go ahead and slip into neutral since no amount of logic and expert citations seem to matter. But that doesn't mean it is a safe choice.

 

[redpoint5]

"Driving as you wish" is my way of surrendering to the straw man posturing present in this thread.

You keep using that phrase. I do not think it means what you think it means.

 

[dandrewk]

"Driving as you wish" is my way of surrendering to the straw man posturing present in this thread.

You keep using that phrase. I do not think it means what you think it means.

Is this a "Trump-like" pivot?

You mean, when I respond to a post advocating the usage of "N" to coast, and then others getting all upset because (they say) I just said that the fabled "coast mode" is unsafe? Yeah, no straw man there.

You and I just disagree. I can live with that. Can you?

 

[redpoint5]

"Driving as you wish" is my way of surrendering to the straw man posturing present in this thread.

You keep using that phrase. I do not think it means what you think it means.

Is this a "Trump-like" pivot?

It was an attempt at humor. It's from the movie The Princess Bride.

You mean, when I respond to a post advocating the usage of "N" to coast, and then others getting all upset because (they say) I just said that the fabled "coast mode" is unsafe? Yeah, no straw man there.

This is what I mean by "not what you think it means". A straw man argument isn't talking about a feature that doesn't exist.
Rather, it is an intentionally misrepresented proposition that is set up because it is easier to defeat than an opponent's real argument.

Here's a recent example:

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??!!"...