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2018 Accord Hybrid EX-L
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Explain how the gas engine can run at full throttle (constant 6200rpm) and combine its power with the electric motor when there's only two fixed gear modes (EV and Direct) via only one lock up clutch between them.
I cannot believe you are a forum moderator Rick, getting away with the responses on the edge and now editing of ones post.

And I'm really tired of hearing long drawn out responses by non-owners who likely never even drove a late gen Honda Hybrid.



Two motors and a eCVT (electronic Continuously Variable TRANSMISSION). Honda could not make this more clear.

Honda calls it an eCVT because most people can't understand the lack of an actual transmission.Transmission in cars refer to something having multiple gears (or infinite in the case of a CVT) to deliver the power from the engine. The Accord Hybrid DOES NOT have a transmission, even C&D broke this down:

Explaining the Honda Accord's Shrewdly Designed New Hybrid System. The headline is "Making It Simple: There's no transmission—really"

And to answer your question how the car can run on both battery and engine at the same time producing peak HP and Torque its explained in the Engineering Explained video starting at 2:15 in the Hybrid mode. The engine turns the generator producing power to the PCU, which combines with the battery powering the PCU to run the electric drive motor to create the peak numbers. Full power is achieved in Hybrid mode.

Honda has a graphic to depict this and you'll notice that the powerflow graphic shows both the battery and engine creating power:



Here's another article again that says it is not a transmission, despite whatever Honda wants to call it. 2014 Honda Accord Hybrid Has No Transmission: How It Works
 

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To try and get away from the more contentious issues of terminology, the more recent posts from Seminole and others point to what is (I think) a fairly neat little bit of technology. Namely, rev-matching, when the clutch engages between the ICE and the traction/drive motor. (Or, depending on how you want to look at it, when the clutch engages between the generator motor that is permanently coupled to the ICE, and the traction/drive motor.)

Since the gear ratios between the traction motor to the wheels is fixed, and there is also a fixed ration between the ICE and the traction motor, once the clutch is engaged, the act of engaging the clutch must (as far as I can tell) be preceded by the gas engine's rpm being raised or lowered to match the current speed of the car. This rev-matching appears pretty seamless in practice, as you don't notice it while driving.

There's nothing really new about rev-matching - some transmissions on gas-engine cars (for example, some exotic sports cars where the "automatic" transmission is really a "self-shifting manual") have been doing automated rev-matching on down-shifts for years. But I'm still impressed.....

In the video with the guy talking in front of a whiteboard, he shows the overall gear ratio from the ICE to the wheels, when the clutch is engaged. It is a number (2.xx) that is fairly close to that of 6th gear in an Accord with six-speed manual. Thus it can be inferred that the actual rpm of the gas engine when cruising down the highway at 65 mph is a pretty low number, perhaps 2,000 rpm, give or take. This is why the gas engine isn't connected to the wheels below 43 mph (or whatever the right figure is), and, conversely, why it can stay connected at higher highway speeds, for passing, etc. But unless you take your hybrid well above 100 mph, you are not getting close to redline of the ICE (and probably the top speed is limited at some point that is also reasonably below redline). This is also one of the reasons why the combined hp of the overall drivetrain is so much less than the sum of the maximum hp figures for the traction motor and ICE, separately.

Note that the ICE is probably revving higher in hybrid-mode, when it is NOT connected to the wheels, in order to get more charging. At least on occasion. (Compared to its relatively low rpm when locked up, at normal highway speeds.)

I kind of wish we could display a tachometer for the ICE, as an option, for those who really want to see what is happening. Or, even better, traction motor rpm AND ICE rpm. My code reader's smartphone app would let me see the ICE rpm, in any case, albeit just on the phone's screen.

Just my speculations, etc..... The topic is interesting to me, just in terms of understanding the technology.
 

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I cannot believe you are a forum moderator Rick
I know, right!? I can't believe it either. It's like a dream!

And I'm really tired of hearing long drawn out responses by non-owners who likely never even drove a late gen Honda Hybrid.
It can be frustrating when others thoughtfully and respectfully counter your statements and interpretation of data. Here they respond with well-thought out arguments and questions. You seem to be focusing on ownership as a means of knowledge. Why fight? Why not post in The Facebook! You can swear, post misleading information, and insult everyone who counters your arguments. (Here it is frowned upon)
 

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Honda could not make this more clear.
Finally, you said something that is correct. From here: "The Accord Hybrid's two-motor hybrid powertrain takes an elegant and innovative approach to hybrid power, eliminating the need for a conventional mechanical transmission."

Or Here: "As before, the Accord two-motor system operates without the need for a conventional automatic transmission." Can't be much clearer than that.

The HAH has a power-train, which Honda calls the "transmission system." It transmits power from the ICE and/or the motor to the wheels. It does not have what your Wikipedia article said was usually called a "transmission," and that Honda called a "conventional mechanical transmission."

And I've driven my 2018 HAH over 4,000 miles now.
 

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Discussion Starter #25
It can be frustrating when others thoughtfully and respectfully counter your statements and interpretation of data. Here they respond with well-thought out arguments and questions. You seem to be focusing on ownership as a means of knowledge. Why fight? Why not post in The Facebook! You can swear, post misleading information, and insult everyone who counters your arguments. (Here it is frowned upon)
No no. I opt focus on known facts whenever possible. Not re-posting the same internet graphics and non-Honda article text over and over and over.

Funny tho, how many of the known facts here are from the Honda's own documentation and are indisputable. Yet some randomly accept or reject Honda's documents, cherry picking only what they want to believe from Honda.

I also give actual driving experience, previously as a long term test driver which you (Rick) poo poo'd in another thread and belittled me. And now as an owner I can speak in great detail and include basic metrics and analytics directly from the car.

Many posting here clearly do not know what they do not know, and they will not realize this until the drive one.

The Full power example I used was never explained despite re-posting the same old videos and Honda documents.

Do non-owners realize that from a stand still, when the Hybrid is floored, the gas engine will quickly jump to 5900-6200 rpm and will not drop until you reduce throttle input? It's much like the 1.5's CVT at full throttle, but does not vary high RPM to mimic a shift point.

Unexplained is how the gas engine combines LIMITED, indirect power with the electric motor (lock up clutch NOT engaged), yet freely rev's, with no transmission involved. This would be Hybrid mode...again no direct drive...no lock up clutch engaged...and nothing yet explains how gas power is combined and power TRANSMITTED to the wheels with electric motor power...if there's no "transmission".

Unexplained is how a series of gears, a high capacity lock up clutch, and more drive components are all found within just one housing assembly, with an ATF fluid level dip stick, and is directly attached to the engine, could possibly contain all of this action and transmission of power....and still some insist its not a transmission.

The term or label of "transmission" and "eCVT" in the Hybrid is used extensively by Honda. Those who wish to challenge this, take it up with Honda and get them to change their verbiage. Until that happens, I stand by Honda's terms, and my statements 100%.
 

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Discussion Starter #26
"The Accord Hybrid's two-motor hybrid powertrain takes an elegant and innovative approach to hybrid power, eliminating the need for a conventional mechanical transmission."

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No one, at any time, has attempted to label the Hybrid transmission as "conventional".
 

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(From) Here: "As before, the Accord two-motor system operates without the need for a conventional automatic transmission." Can't be much clearer than that.
No one, at any time, has attempted to label the Hybrid transmission as "conventional".
You did:

This basic definition is what I go by, which is what is taught in high school and college.
Note three parts of this definition. First, it is a machine; a mechanical device. Second, that is only a part of the transmission system. Third, that the term "transmission" is often (i.e., "traditionally") used to refer to the mechanical device ("machine") that converts rotating power from one device to another.

The HAH has no such mechanical device. When the clutch is engaged, the ICE drives the wheels without any such conversion. When it is not engaged, it drives only the generator. The electrical circuits that transfer that power do not qualify as a "machine," and so are not a transmission by the definition you "go by."

The lack of such a mechanical device is what Honda, and all those "video experts" (some of whom who have actually dissected the system) mean when they say the HAH has no transmission. You must know this, yet you refuse to acknowledge it. When they say the HAH has an eCVT, they are referring to the entire transmission system. Not to the traditional "transmission," or anything that fits the definition you "go by." You are wrong, thrice, when you claim that the HAH has a transmission that fits that definition.
 

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Engine Drive Operation
When cruising at medium to high speeds, the high-efficiency Atkinson-cycle i-VTEC gasoline engine provides propulsion via a high capacity lock-up clutch, which connects the generator motor (always linked to the engine) and the electric drive motor, effectively sending motive power directly from the engine to the drive wheels. In this type mode, the system works as a "parallel hybrid" where both the gasoline engine and, when required – for instance upon quick acceleration – the electric propulsion motor, both provide power to the wheels. The i-MMD powertrain operates without the use of a conventional transmission.

2018 Honda Accord Press Kit - Powertrain - Model Press Kit - Honda News



Parallel Hybrids: Parallel hybrids use an internal combustion engine (ICE) and electric motor/generator(s) to simultaneously provide power to the wheels through the vehicle's transmission. In addition to supplementing the power of the engine, the motor/generator can also charge the hybrid battery while the vehicle is in motion. Driving the vehicle with only the motor/generator is also possible. An example is the Honda Integrated Motor Assist (IMA) hybrid system.

https://www.searchautoparts.com/motorage/undercar-service-repair/technical-look-parallel-axis-hybrid-transaxles






Honda's statement above explains high speed cruising and acceleration VERY well. And I'll try to explain one last time, there is missing information in regards to exact functionality within the TRANSMISSION when "quick acceleration" occurs at all speeds. During "quick acceleration" it goes into Hybrid mode. Both gas engine and electric motors are functioning. However, the lock up clutch is NOT engaged, the gas engine is NOT in direct drive, regardless of speed during quick acceleration. I previously mentioned "lock up" being very sensitive to load and is quick to disengage at speed.

Short story;
During quick acceleration, the gas engine freely winds up in Hybrid mode, regardless of speed. There is no direct connection to anything but the generator. The gas engine has only one known connection to the wheels, via lock up clutch. When the clutch is NOT engaged, the gas engine is still able to combine a small amount of power with the electric motor.


I do not expect Google search experts to know all the answers, and please stop trying by re-posting all the same old stuff. I only press so hard because I find all this functionality is simply amazing without a transmission. Ha!
 

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2018 Accord Hybrid EX-L
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I’ve posted two times how the motor can power the wheels in hybrid mode without the clutch being engaged, and how that doesn’t use a transmission, so I’ll try one last time. The motor spins a generator, creating electricity. The faster the motor spins the generator the more power it creates, that’s how you get your “screaming at 6200rpm” situation. So now you got a generator making power that has to go somewhere. It goes to one of the two PCUs. The other PCU gets power from the battery. Those both deliver power to the electric motor which powers the wheels. This is full power mode. When the battery alone is powering the one PCU and then the electric motor is when it produces the 180ish hp and 232lbf of torque. Add in the engine producing power to the second PCU and you get the full HP and torque. In this mode the engine is providing power to the wheels THROUGH the electric motor, it is not directly connected though. Go back to my post number 22 and read the third column.

Here's an illustration:



Your photo above states this exact operation. You highlight “transmission” but it clearly says that the “transmission” is the electric motor, the mentions the lockup clutch.

Your quote about parallel hybrids is outdated as that talks about the OLD IMA system which yes, used an actual transmission just like the Toyotas do. Honda even put parallel hybrid in quotes in your first paragraph because the drivetrain is working in theory like a parallel with both the gas and battery creating power BUT they are both routing that power to an electric motor which is the only way it gets to the wheels.

So there is no CVT in the Accord. It has a single speed gear off the electric motor like every other electric car and the lockup clutch that is it. Because the PCUs combined with the electric motor ACTS like a transmission where they can control the output from the gas motor and the battery across various outputs and speeds Honda calls it an eCVT but it is not a CVT in the traditional sense.

You seems to keep harping on that a transmission is anything that transmits power. If that’s the case then you are forgetting about the four transmissions the car has called wheels that transmit the power from the engine to the road, or the transmissions in the window regulators, or the tons of other things in a car that transmit power from a motor to some function of the car. This is just playing semantics.

The fact remains that when using the word transmission in a car it refers to something that has multiple gears or variable gears like in a CVT to manage engine output across a variety of speeds and rpms. There is nothing in the Accord that does this. Everything is a fixed ratio from the lockup clutch, to the electric motor, therefore the Accord does not have a transmission. These “transmit” the power to the wheels and the ground but they are not a transmission.

The most simple way to think of it is that the Accord is an electric car like a Tesla where there is a single speed motor that spins faster or slower depending on the need you want. This motor unlike a full EV get its power from the battery or the engine, or BOTH. The Accord is basically a serial hybrid. Only under special circumstances does the lockup clutch engage and can the engine directly power the wheels, that one function is what makes it unique from a pure serial hybrid.
 

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Discussion Starter #30
....that’s how you get your “screaming at 6200rpm” situation. So now you got a generator making power that has to go somewhere. It goes to one of the two PCUs. The other PCU gets power from the battery. Those both deliver power to the electric motor which powers the wheels. This is full power mode. When the battery alone is powering the one PCU and then the electric motor is when it produces the 180ish hp and 232lbf of torque. .
Your long post is mostly right, but your explanation of full power mode is not right.

Yes, the electric motor tops out at 181hp and is not efficient at high speed because it draws a huge amount of power.

Yet we get a combined (gas+electric) total of 212hp without a "transmission"? So, added power beyond the electric motor's output without the gas engine not being mechanically engaged (but it can be)...and still no transmission. Those gears, clutch, so much more all in the same sealed housing transmitting power to the wheels....nope...still no a transmission. LOL! Comical!


Honda labels the "assembly" in question as a transmission and eCVT. Only internet articles exclude, WHILE QUALIFYING, it has no CONVENTIONAL transmission. "No Transmission" is click bait.


Again, if you don't like the terminology used by Honda, take it up with HONDA.

But you nor anyone else well. The debate that isn't, rocks on.
 

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Honda's statement above explains high speed cruising and acceleration VERY well.
The first one does. But it has nothing to do with your misconceptions about what people mean when they say the 2017+ HAH does not have a transmission. They mean a mechanical device that lets you vary how ICE rpms are converted mechanically into wheel rpms.

The second one refers to an older hybrid system, called IMA. The 2017+ HAH uses i-MMD. Maybe you should sharpen your own google-search skills. When written, it may have been true that almost all parallel hybrids used a transmission. But that is not a part of what it means to be a parallel hybrid.

And I'll try to explain one last time, there is missing information in regards to exact functionality within the TRANSMISSION when "quick acceleration" occurs at all speeds. During "quick acceleration" it goes into Hybrid mode. Both gas engine and electric motors are functioning. However, the lock up clutch is NOT engaged, the gas engine is NOT in direct drive, regardless of speed during quick acceleration.
And the part you put in red is exactly where you are wrong. And where you refuse to see what others are trying to explain to you. The criteria used to define “quick acceleration” is that the power required makes the clutch lock up. If it doesn’t lock up, that description does not apply.

The 2017+ HAH has two hybrid modes:
  • Serial mode is when the clutch is not engaged. ICE power is transferred mechanically to the generator at a fixed gear ratio. The generator’s electric energy is sent to the motor though the PCU. And The motor alone drives the car.
  • Parallel mode is when the clutch is engaged. ICE power is transferred mechanically to the same shaft the motor uses, also at a fixed gear ratio. Excess power may be funneled off by the generator, which is not disengaged. Or maybe even by the motor (I won’t claim to know what I don’t, as you do.) Shortfalls in power are provided by the motor, powered by the battery and/or the generator.
Nowhere in either process is there a mechanical device that can vary the gear ratio that I called “fixed.” Since such a device is what people mean when they say “the transmission,” we can truthfully claim that the 2017+ HAH has no transmission. Even if Honda calls the entire system an eCVT.

I previously mentioned "lock up" being very sensitive to load and is quick to disengage at speed.
Exactly. When the acceleration is no longer “quick.”

I do not expect Google search experts to know all the answers, and please stop trying by re-posting all the same old stuff.
Then try reading/listening to it. I’ll even give you an Easter Egg: there is one point not well explained in the EE video, that potentially could explain meter readings you think mean something that we say they don’t. I’ve even tried to get EE to explain it, but they haven’t.

BUT IF IT IS TRUE, IT STILL DOESN’T QUALIFY AS A TRANSMISSION.

So maybe you should try being less combative, and ask questions about what you don’t understand instead of insisting that others are wrong about what you don’t understand.

Yet we get a combined (gas+electric) total of 212hp without a "transmission"?
Horsepower=Torque(in ft-lb)*RPM/5252. The numbers you quote were evaluated independently for the two power plants, in isolation from each other. And at the maximum that each can produce. When in parallel hybrid mode, they will not be operating at the parameters used in those measurements. That’s why you can’t just add horsepower ratings. The two plants, working together sans transmission(s), generate a com
 

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2018 Accord Hybrid EX-L
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JeffJo did a better job of explaining what I was trying to say. I was unaware the clutch could be engaged with the electric motor also providing power at the same time. That is the power mode you are looking for and the two videos below explain it.

But they also explain that fact of the matter is there is nothing in the entire drivetrain that can vary gearing. All of it is fixed single speeds. The whole system working in concert is what is called an eCVT. If you want to keep harping on Honda calling it an eCVT and emphasising the T then we can't do anything for you. Nobody is arguing that there are different fixed gears to transmit power from the motor or the generator to the wheels, but those are not a traditional transmission in the sense of the word.

Watch this until 2:32:

https://youtu.be/iGYg-CSO9w8?t=113


Then watch this:



There are multiple sources which explain that the action of the entire system working together is called "eCVT".

"Electric Continuously Variable Transmission - The Accord Hybrid is not equipped with a conventional physical transmission. Instead, the Electric Continuously Variable Transmission (E-CVT) consists of the interaction of the Accord Hybrid's gasoline engine and two electric motors. Coordinated by the IPU, the E-CVT offers smooth and predictable acceleration matched with efficient low-rpm highway cruising when the gasoline engine is in operation. Gasoline engine shutdown is seamlessly integrated into the operation of the Accord Hybrid when appropriate.": Honda?s Excellent Two-Mode Hybrid System Wins GCJ Technology Award | CleanMPG

"What’s clever about Honda’s latest innovation is that it has no transmission. At least, none in the conventional sense. There are four gearsets between the electric and combustion power sources and the front wheels, but all drive ratios are fixed. The compound powertrain provides three standard propulsion modes—electric-only, gasoline-only, and blended gas and electric—without shifting gears or varying a planetary ratio. ": https://www.caranddriver.com/features/explaining-the-honda-accords-shrewdly-designed-new-hybrid-system-tech-dept

Also the picture labeled eCVT that you posted in post 21 is the two motor unit housing:

 

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Discussion Starter #33
During "quick acceleration" it goes into Hybrid mode. Both gas engine and electric motors are functioning. However, the lock up clutch is NOT engaged, the gas engine is NOT in direct drive, regardless of speed during quick acceleration.


And the part you put in red is exactly where you are wrong. And where you refuse to see what others are trying to explain to you. The criteria used to define “quick acceleration” is that the power required makes the clutch lock up. If it doesn’t lock up, that description does not apply.
Nope. You are very wrong and have a server lack of understanding.

I refuse to respond to all these drawn out responses assuming I do not know what I'm talking about. I actually do, and you should take my posts a little more seriously, and stop taking SO many of my statements taking ridiculously out of context.

But THIS...this statement in RED above that I have made more than once, needs to be pounded into all of you. If you guys would understand just this one FACT...we'd make serious progress here.



It is IMPOSSIBLE....I say again....IMPOSSIBLE...for the lock up clutch to be engaged when the engine is running at high RPM. This is easily explained AND proven. I've done both.



HINT: Quickly accelerate or full throttle from 65mph, ICE hits 5900-6200 RPM. If the direct drive lock up clutch (fixed gearing) remained engaged, the ICE could not freely rev.

HINT: The gas engine, if lock up clutch was engaged when running at 6200rpm, you will be WELL over the 114mph governed speed.

HINT: Quickly accelerate from 65mph and 2500RPM. Gas RPM's jump. (If the DIRECT drive lock up clutch remained engaged, gas engine RPM's would change slowly only as wheel speed increases.)

HINT: Dramatically vary throttle input during quick acceleration and watch gas engine RPM's VARY while wheel speed does NOT.
(Reality...and impossible if the lock up clutch was engaged.)


I am starting to believe you guys have conspiracy theory and really "want to believe" in "no transmission". If not a fun internet conspiracy, than its absolute delirium. And I cannot deal with that. Peace out!

 

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During "quick acceleration" it goes into Hybrid mode. Both gas engine and electric motors are functioning. However, the lock up clutch is NOT engaged, the gas engine is NOT in direct drive, regardless of speed during quick acceleration./COLOR]

Let’s actually look at the source for this bit of information you are misinterpreting, with some comments about what you are (intentionally?) overlooking :
Engine Drive Operation
When cruising at medium to high speeds[1], the high-efficiency Atkinson-cycle i-VTEC gasoline engine provides propulsion via a high capacity lock-up clutch[2], which connects the generator motor (always linked to the engine) and the electric drive motor, effectively sending motive power directly from the engine to the drive wheels. In this type mode, the system works as a "parallel hybrid"[3] where both the gasoline engine and, when required – for instance[4] upon quick acceleration – the electric propulsion motor, both provide power to the wheels. The i-MMD powertrain[5] operates without the use of a conventional transmission.[6]​

  1. The example that follows applies when you already traveling at a speed sufficient for the clutch to be engaged. Not to when the clutch is unlocked, or to a transition from an unlocked clutch to a locked clutch.
  2. See? They even say explicitly that they are talking about when the clutch is already locked up.
  3. ”Parallel hybrid” means that both the motor, and the ICE, are applying torque to the drive wheels at the same time. That is, the clutch is locked up. This is the only way that the ICE drives the wheels.
  4. ”For instance” means that this is the example that applies at higher speeds, not a description of every quick acceleration from any speed. Specifically, it is describing what happens if you need acceleration when the clutch is already locked up, and it stays locked up.
  5. The “i-MMD power train” includes the ICE+generator linkage and the clutch. But this is now describing the system itself, not any state of the system (locked or unlocked).
  6. A “conventional transmission” is any mechanical device that varies the mechanical gear ratio from the power plant to the wheels. Whether it uses a gearbox, belts, or a torque converter, it is a “conventional transmission.” The system as a whole does not use one. That's all the statements you say are untrue mean.
Salient points: The description of "quick acceleration" here applies to parallel hybrid mode only, and Honda specifically says that the i-MMD does not use what is conventionally called a transmission. You have misrepresented both of these points.

You are very wrong and have a server lack of understanding. …
Nope. You use selective misinterpretation to arrive at the conclusion you want.

… stop taking SO many of my statements taking ridiculously out of context.
Where you think I did that, I was trying to show you how you are doing it. Now, I’m not an expert in any of this, but I do know how to read, how to see context, and to see how it is not seen by others.

Try taking your own advice.

It is IMPOSSIBLE....I say again....IMPOSSIBLE...for the lock up clutch to be engaged when the engine is running at high RPM.
Since my HAH does not have a tachometer (yours does?), I can’t verify your assertion that the engine is revving that high. But if your ICE does, then you are correct that it means the clutch has become disengaged. It should have been engaged before you accelerated from 65 mph, and now it is not. SO, the i-MMD is operating in serial hybrid mode, not parallel mode, and the issue of a transmission is irrelevant since the ICE is not driving the wheels.

(HINT: It is driving the generator, not the wheels. The electricity from the generator is sent, by the PCU, to the motor and/or the battery. Your horsepower is that of the motor alone, 181 HP I believe. I'm not sure why the computer would do this, since it gets 212 HP if it doesn't disengage. But I try not to explain things I don't know.)

(Hint: Since the ICE is not driving the wheels, there is no definable gear ratio. Let alone a variable one, or anything that could be called a transmission. Yes, you can divide one's RPM by the other's. But I can also divide the number of apples in a pie by the number of oranges it takes to make a pitcher of juice. The result is irrelevant.)

(Hint: See what I did there?)
 

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Yes. I see you are more wrong than ever before.
Odd that I pointed out your mistakes explicitly, and all you can do is assert that I was wrong.

Again, try taking your own advice. Look for the context of the statement you are citing, accepting the possibility that you misinterpreted it. Then either confirm or disprove the interpretation to yourself.
 

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Worried about my Third Party Warranty Plan now...
Does the Honda Limited Warranty refer to "it" as the Hybrid Powertrain?
At this point, I want to make sure I have a comprehensive enough plan. I advised Assurant (3rd party warranty company) that the my vehicle does not have a transmission, because that's what my salesman told me.
I suppose I can call Assurant for clarification and to make sure I have coverage for the Hybrid Powertrain and/or transmission.
Thanks for bringing up this topic...and for everyone's insight.
Happy Holidays.
 

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Discussion Starter #38
Worried about my Third Party Warranty Plan now...
Does the Honda Limited Warranty refer to "it" as the Hybrid Powertrain?
At this point, I want to make sure I have a comprehensive enough plan. I advised Assurant (3rd party warranty company) that the my vehicle does not have a transmission, because that's what my salesman told me.
I suppose I can call Assurant for clarification and to make sure I have coverage for the Hybrid Powertrain and/or transmission.
Thanks for bringing up this topic...and for everyone's insight.
Happy Holidays.
Can't comment on 3rd party coverage, but HondaCare covers it. And a lot is covered under the Fed's 8 year/100mile warrenty for Hybrids and Electric cars.


Underneath the "Hybrid Battery" line items, says "HYBRID TRANSMISSION ASSEMBLY"




 

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It seems that one of the main bones of contention (ignoring whether the term "transmission" applies to the i-MMD system or not) has to do with what happens when you are cruising down the highway (at 65 mph, say), and then mash the throttle.

Before you mash the throttle, the lock-up clutch is engaged, so the ICE is connected to the road wheels, and running (approximately) at 2,000 rpm, or so. More or less at the same rpm it would run if you had a gas-only car, with a manual transmission, in top gear (6th, say).

The traction electric motor is also connected to the wheels, and the relative horsepower and torque contributions between the two sources of power and torque are not obvious.

But, even if "full-throttle" fuel was supplied to the ICE, it would only be providing something like 50 hp (at around 2,000 rpm), as hp is basically torque x rpm. (Versus its hp rating at 6200 rpm of 143 hp.)

The same "hp = torque x rpm" definition also applies to the traction motor, so it is also limited (roughly) to providing 1/2 to perhaps 2/3 of its max hp rating of 180 hp. (It's not clear at what percentage of "redline" the traction motor is running, at 65 mph. But if the car can do 114 mph, it is presumably running at no more than 65/114 of it's "redline".)

Cruising along at 65 mph doesn't require much power, however. So before you mash the throttle, neither the ICE nor the traction motor are being run at max. torque (and therefore aren't even at their maximum potential hp output at their current rpms). Basically using less gas fuel than the ICE could make use of, and also consuming less electric power than the traction motor could....

When you mash the throttle, the drive-train computer(s) have to decide whether it is better to leave the ICE connected, contributing its torque at 2,000 rpm or so, or disconnect it, so that maximum electrical power can instead be fed to the traction motor, with the ICE revving up. RinconVTR says this is what happens (presumably by using his ears to hear the revving of the ICE, or perhaps he is using a code reader and app to actually monitor the ICE rpm). I don't doubt that he is correct in this. It may also be true that under less-than full-throttle acceleration, the computer(s) decide that it is sufficient to leave the ICE connected. Whether that also happens on occasion, I can't say.... (Although, it IS something I will probably pay more attention to from now on!) And maybe what happens is a bit different in the various modes, especially Sport mode....

My main point, I suppose, is that the hp being provided by both ICE and traction motor, when the ICE is coupled to the wheels, is limited in both cases by the "less than redline" rpm of both power sources (connected to the wheels at their respective fixed ratios), to well below their individual max hp ratings. It is not clear at what road speed (which implies a specific ICE rpm, as well as a specific traction motor rpm) you get the supposed combined hp of 212. But it would be at relatively high road speed, I think, possibly at the limited maximum speed of the car (which I think RinconVTR said was 114 mph)?

Actually, even at the limited max. speed (114 mph, say), the ICE is still well below redline, I think. If the fixed ratio between the ICE and the wheels (when coupled) was made numerically higher (more like 4th gear in a manual, versus 6th), then you would get more hp contribution from the ICE, when coupled, and, I think, a noticeably higher max combined hp rating. But this would result in somewhat worse highway mileage rating, faster wear on the ICE, more ICE noise when cruising down the highway, etc. So Honda has decided to keep the one fixed ratio relatively "tall", even if it limits the maximum combined hp of the drivetrain. It's worth noting that Honda quotes the same 212 combined hp rating for the plug-in hybrid Clarity, which has the same traction motor, but only a 1.5 liter ICE, rated at only 103 hp.

As a side comment, the faster you are going to begin with, the more likely it will be for the computer(s) to decide to leave the ICE connected, if for no other reason than the hp from the ICE will be higher, at those higher road speeds. And the ICE will still be (probably) at close to maximum torque. So, mashing the throttle at 90 mph is (I think) less likely to result in the ICE becoming uncoupled, than it would be at 65 mph.

As ANOTHER side comment, is also my opinion that arguing about whether our cars have a transmission or not is fairly pointless, especially when "both sides" seem to mostly (OK, maybe not entirely) have the same understanding of what is going on in the drivetrain. Sort of a "you say to-MAY-to, and I say to-MAH-to" type of thing. Can't we all get along? :angel
 
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