Dual vs Quad motor pros and cons?

[Olsonsolar]

Torque vectoring would take a hit, as would the life of your brakes compared to a QM. The positive is potential for a fully locking differential with the DM.

How would brakes take a hit with the dual? I don't see that.

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[crashmtb]

How would brakes take a hit with the dual? I don't see that.

cars with brake based torque vectoring tend to eat brakes…because the brakes have extra work to do.

 

[Bee]

I haven’t gotten to drive an R1 off road yet, but I wonder if a lot of this comes down to technique.

Our Land Rover has computer controlled locking diffs center and rear plus traction control in front. It seems to work best with light to moderate throttle which remains steady. If there is no progress then gently ramping up the throttle gets things moving. I think this gives the computer time to determine where there is traction and where there isn’t, then adjust the diffs and front brakes to optimize power delivery. Newer Land Rovers have all terrain progress control (ATPC) which is like very low speed cruise control where you can set a speed and let the vehicle apply as much throttle as is required to maintain that speed.

I would expect a Rivian to adapt faster, but I suspect there is still a delay. Plus if people see no progress and let off the throttle then they’re working against the vehicle by not giving it enough power to the appropriate wheel(s). Something like Land Rover’s ATPC would help folks who aren’t used to this driving style. Because there is no engine noise, it might be nice if a Rivian system like this displayed the percentage of throttle being used to help us understand what it takes to get results.

I mean, it's kind of hard to think this won't be sorted over time with software adjustments and changes in psychology, right? Just, it was very emotional the first time I saw a Rivian not spin a wheel and I'm having a hard time getting over that, man. And it keeps happening, reviewer after reviewer intentionally puts it in a traction situation and it's like "oh hey look that wheel isn't spinning."

What I don't understand is shouldn't it be pretty easy to give us a "locked diff" mode? Like you guys want to work out the better "we're sensing the wheels and adjusting" thing out over time? I'm even happy to play with that over time and help you test it. But give me a dumb button. Clearly you're capable of detecting my accelerator pedal input and distributing that power across all 4 wheels evenly, right? Let's start there.

I just don't need the size of an R1S over a Rubicon 4xE, like I really find the 4Runner attractive but I'm not shopping that, right? Before I plopped a reservation down on a Rivian I was waffling between a Gladiator vs. Wrangler Rubicon so I could pretend like I'm going to do things that gets me stuck in places because I used to do things like that in a former life.

All joking aside, I'm trading weight and size for something, that something is a BEV offroader with interesting technical upsides. If you remove the interesting technical upsides and instead make that a mark against it being an off roader, what am I really doing? We're a 2 BEV household, I can keep 99% of the non-road trip miles electric in a Wrangler 4xE and retain all the benefits of having a gas engine AND still come in lighter AND be a Wrangler Rubicon, which, is, a Wrangler Rubicon. C'mon Rivian, sort this, I want the R1x to be amazing.

Some people want/need for aliens to be real, I have that kind of feeling a little bit for this truck and it being amazing.

 

[Rivian_Hugh_III]

I once emailed RJ about an auditory signal for wheel-speed/wheel-power in off-roading conditions.

People were complaining that they couldn’t hear the engine noise to know what was happening with power to the wheels.

My suggestion was to use the sound system to generate a wave interference pattern with changing harmonics that would indicate the level of power to the wheels.

In this system, several speakers would generate a low and steady rumble. This could be subtle. Several,other speakers would generate a variable rumble, beginning at the same hertz when the gas pedal is neutral, but slowly increasing hz as the accelerator is depressed.

This would create an interference pattern in the sound waves which would be heard as a slow or fast pairing of peaks reinforcing, troughs reinforcing, and peaks and troughs offsetting.

Amy musician who has tuned an instrument would understand this immediately.

The idea may not be enjoyable in actual practice, or it might, but it would certainly be practical and would provide auditory feedback to an off-road driver wanting data on power to wheels.

 

[jclicky]

I haven’t gotten to drive an R1 off road yet, but I wonder if a lot of this comes down to technique.

Our Land Rover has computer controlled locking diffs center and rear plus traction control in front. It seems to work best with light to moderate throttle which remains steady. If there is no progress then gently ramping up the throttle gets things moving. I think this gives the computer time to determine where there is traction and where there isn’t, then adjust the diffs and front brakes to optimize power delivery. Newer Land Rovers have all terrain progress control (ATPC) which is like very low speed cruise control where you can set a speed and let the vehicle apply as much throttle as is required to maintain that speed.

I would expect a Rivian to adapt faster, but I suspect there is still a delay. Plus if people see no progress and let off the throttle then they’re working against the vehicle by not giving it enough power to the appropriate wheel(s). Something like Land Rover’s ATPC would help folks who aren’t used to this driving style. Because there is no engine noise, it might be nice if a Rivian system like this displayed the percentage of throttle being used to help us understand what it takes to get results.

This is what I’ve seen/heard/read too. There’s a specific moment in one of @OutofSpecKyle’s early R1T off-road videos where he’s observing another owner drive his R1T (this was before Kyle had his I think) & they concluded that counterintuitively you had to change your technique of driving & give it more “gas” to help the computer adjust & figure it out.

In some of the more recent Overlanding out of spec reviews Kyle has reiterated that the Rivian just needs more of a heavy foot to accomplish the same effect that pedal-pumping accomplishes on an ICE.

I also believe that software updates can help, but I think a ton of people are holding out too much hope for software. It will require a new technique of driving wherein you give the car more “gas” than would ever be prudent on an ICE, that is until Rivian ever adds toggles equivalent to front & rear differentials, which could be added.

 

[SoCal Rob]

I mean, it's kind of hard to think this won't be sorted over time with software adjustments and changes in psychology, right? Just, it was very emotional the first time I saw a Rivian not spin a wheel and I'm having a hard time getting over that, man. And it keeps happening, reviewer after reviewer intentionally puts it in a traction situation and it's like "oh hey look that wheel isn't spinning."

What I don't understand is shouldn't it be pretty easy to give us a "locked diff" mode? Like you guys want to work out the better "we're sensing the wheels and adjusting" thing out over time? I'm even happy to play with that over time and help you test it. But give me a dumb button. Clearly you're capable of detecting my accelerator pedal input and distributing that power across all 4 wheels evenly, right? Let's start there.

I just don't need the size of an R1S over a Rubicon 4xE, like I really find the 4Runner attractive but I'm not shopping that, right? Before I plopped a reservation down on a Rivian I was waffling between a Gladiator vs. Wrangler Rubicon so I could pretend like I'm going to do things that gets me stuck in places because I used to do things like that in a former life.

All joking aside, I'm trading weight and size for something, that something is a BEV offroader with interesting technical upsides. If you remove the interesting technical upsides and instead make that a mark against it being an off roader, what am I really doing? We're a 2 BEV household, I can keep 99% of the non-road trip miles electric in a Wrangler 4xE and retain all the benefits of having a gas engine AND still come in lighter AND be a Wrangler Rubicon, which, is, a Wrangler Rubicon. C'mon Rivian, sort this, I want the R1x to be amazing.

Some people want/need for aliens to be real, I have that kind of feeling a little bit for this truck and it being amazing.

I think a locked diff mode where all 4 wheels spin at the same speed no matter what could put some real stress on the driveline components and the engineers are confident they have a more elegant solution than a brute force approach like that.

Did you watch the video from @OutofSpecKyle where the R1T and R1S were being compared on the same trail? The first thing he did with both was test a particularly tough uphill stretch at a very low speed and the R1T got stuck with, if I recall correctly, a couple wheels spinning and a couple remaining stationary.

I was very disappointed to see that.

Later, when preparing to do the main run, he put the vehicle in Rock Crawl mode. Wait, what now? I had to go back to make sure I heard that right. Maybe Rivian’s guidance is different (or non-existent) but I would have had our Land Rover in Rock Crawl as soon as I had an issue with traction on a mix of dirt and rock at a crawling speed. I wish he’d duplicate the test in his R1T but in Rock Crawl as soon as he encounters an issue with traction.

I really think a lot of this comes back to using the right settings for the conditions and obstacles like I was talking about here. Rivian really needs a video showing what changes in each drive mode and why it’s important to select the right one. I’m looking forward to getting our R1S so I can do some testing of my own. I am pretty sure that our LR3 will have already trained me well for Rivian’s way of doing things.

edit: typos

 

[Bee]

I think a locked diff mode where all 4 wheels spin at the same speed no matter what could put some real stress on the driveline components and the engineers are confident they have a more elegant solution than a brute force approach like that.

Did you watch the video from @OutofSpecKyle where the R1T and R1S were being compared on the same trail? The first thing he did with both was test a particularly tough uphill stretch at a very low speed and the R1T got stuck with, if I recall correctly, a couple wheels spinning and a couple remaining stationary.

I was very disappointed to see that.

Later, when preparing to do the main run, he put the vehicle in Rock Crawl mode. Wait, what now? I had to go back to make sure I heard that right. Maybe Rivian’s guidance is different (or non-existent) but I would have had our Land Rover in Rock Crawl as soon as I had an issue with traction on a mix of dirt and rock at a crawling speed. I wish he’d duplicate the test in his R1T but in Rock Crawl as soon as he encounters an issue with traction.

I really think a lot of this comes back to using the right settings for the conditions and obstacles like I was talking about here. Rivian really needs a video showing what changes in each drive mode and why it’s important to select the right one. I’m looking forward to getting our R1S so I can do some testing of my own. I am pretty sure that our LR3 will have already trained me well for Rivian’s way of doing things.

edit: typos

In your defense, we said those things before he posted that video, lol. I hear you about the power locking the 4 wheels and I backspaced over several solutions as I was making my previous post but some kind of pseudo "first gear" that maybe only has like 25% power down to the floor could work. It gets very speculative, but my overall point is there is a dumb solution there we can probably come up with in 5 minutes.

Am I wrong? I'm ok with being wrong, it would be a problem if I wasn't at this stage of my life seeing as it's kind of my default position.

 

[SoCal Rob]

This is what I’ve seen/heard/read too. There’s a specific moment in one of @OutofSpecKyle’s early R1T off-road videos where he’s observing another owner drive his R1T (this was before Kyle had his I think) & they concluded that counterintuitively you had to change your technique of driving & give it more “gas” to help the computer adjust & figure it out.

In some of the more recent Overlanding out of spec reviews Kyle has reiterated that the Rivian just needs more of a heavy foot to accomplish the same effect that pedal-pumping accomplishes on an ICE.

I also believe that software updates can help, but I think a ton of people are holding out too much hope for software. It will require a new technique of driving wherein you give the car more “gas” than would ever be prudent on an ICE, that is until Rivian ever adds toggles equivalent to front & rear differentials, which could be added.

The Rivian may require a heavier foot on the accelerator to accomplish the same thing no matter what (I’ve seen people mentioning a longer pedal travel) or it could be a matter of which drive mode is selected. In our LR3 the Rock Crawl mode (at a bare minimum) reduces the throttle response so that the vehicle is easier to control. If you picture going over very rocky terrain, there can be a lot of bouncing. On our previous vehicle the bouncing meant that even my right leg was bouncing causing unintended fluctuations in engine speed. Even a little accelerator movement could make a difference at such a low speed. Apparently I wasn’t the only one with this issue so when Land Rover had an electronic throttle they could control they remapped it when conditions warranted.

The only way our Land Rover knows the conditions is by me turning a little knob to select the right drive mode. Rivian makes you tap a touch screen but so far it seems like the same basic strategy applies. Maybe some future OTA upgrade will allow Rivians to use the front facing camera and prompt the driver to change. Maybe a message pops up on the display, “It looks like you’re driving in rough terrain at low speed. Change to Rock Crawl mode?” With buttons for yes, no, and stop asking me so you’d have to turn terrain suggestions on in Settings somewhere. Hopefully less annoying than Clippy, if anyone remembers this:

 

[SoCal Rob]

In your defense, we said those things before he posted that video, lol. I hear you about the power locking the 4 wheels and I backspaced over several solutions as I was making my previous post but some kind of pseudo "first gear" that maybe only has like 25% power down to the floor could work. It gets very speculative, but my overall point is there is a dumb solution there we can probably come up with in 5 minutes.

Am I wrong? I'm ok with being wrong, it would be a problem if I wasn't at this stage of my life seeing as it's kind of my default position.

I am 100% confident that having this kind of power available at each wheel with the ability for the computer to precisely control that power is going to make for outstanding off-road capabilities. The issue is do we need to learn different techniques, does Rivian need to change/add drive modes, or both?

So far I think the Rivian is probably very capable provided the driver makes the right choices with the vehicle config. I just wish they’d take an R1 to some off road or OHV playground area with a mix of conditions and do a full demo to show people coming from Tacomas, Wranglers, etc. how they need to setup the vehicle. It could probably be used for marketing as much as driver training. I’d definitely make sure reviewers watched it if they don’t get something like that already.

Given the time of year, I hope they start with showing people how to configure for snow and also for ice. If they need to develop a new mode for either/both then that really should be a priority because winter driving capability is supremely important for a lot of people. Winter driving needs to be perfected before they dig into off-road adventuring much deeper, in my opinion. At least until the spring.

 

[Bee]

I am 100% confident that having this kind of power available at each wheel with the ability for the computer to precisely control that power is going to make for outstanding off-road capabilities. The issue is do we need to learn different techniques, does Rivian need to change/add drive modes, or both?

So far I think the Rivian is probably very capable provided the driver makes the right choices with the vehicle config. I just wish they’d take an R1 to some off road or OHV playground area with a mix of conditions and do a full demo to show people coming from Tacomas, Wranglers, etc. how they need to setup the vehicle. It could probably be used for marketing as much as driver training. I’d definitely make sure reviewers watched it if they don’t get something like that already.

Given the time of year, I hope they start with showing people how to configure for snow and also for ice. If they need to develop a new mode for either/both then that really should be a priority because winter driving capability is supremely important for a lot of people. Winter driving needs to be perfected before they dig into off-road adventuring much deeper, in my opinion. At least until the spring.

Are you 100% right now, for real? I'm not. I'm confident, but not 100%. I would have thought of all the things to make sure they nail, this would be it and it's slightly confidence shaking that is hasn't.

I've said twice already that I kind of want a 4xE Rubicon on this thread and no one has fought me on it on the grounds I've presented, that's even more confidence shaking. I'm in fanboy ground zero asking for it and everyone is kind of like, "yeah you're not exactly saying crazy things."

 

[Dark-Fx]

This is what I’ve seen/heard/read too. There’s a specific moment in one of @OutofSpecKyle’s early R1T off-road videos where he’s observing another owner drive his R1T (this was before Kyle had his I think) & they concluded that counterintuitively you had to change your technique of driving & give it more “gas” to help the computer adjust & figure it out.

In some of the more recent Overlanding out of spec reviews Kyle has reiterated that the Rivian just needs more of a heavy foot to accomplish the same effect that pedal-pumping accomplishes on an ICE.

I also believe that software updates can help, but I think a ton of people are holding out too much hope for software. It will require a new technique of driving wherein you give the car more “gas” than would ever be prudent on an ICE, that is until Rivian ever adds toggles equivalent to front & rear differentials, which could be added.

I think part of it is the throttle mapping changes in off road modes versus the standard modes, and actually does require more pedal input to get the same amount of power out of the vehicle. Since there isn't any kind of an audible feedback under stall/slow conditions, it's obviously hard to gauge it.

 

[Dark-Fx]

I've said twice already that I kind of want a 4xE Rubicon on this thread and no one has fought me on it on the grounds I've presented, that's even more confidence shaking. I'm in fanboy ground zero asking for it and everyone is kind of like, "yeah you're not exactly saying crazy things."

I just wasn't going to acknowledge your comment because it was so wrong

 

[MountainBikeDude]

I think part of it is the throttle mapping changes in off road modes versus the standard modes, and actually does require more pedal input to get the same amount of power out of the vehicle. Since there isn't any kind of an audible feedback under stall/slow conditions, it's obviously hard to gauge it.

I know we've been down this road before (pardon the pun) but they don't need audible noises in the cab, all they have to do is implement the real-time power guage in the corner of the drive mode video. They had it originally in the UI demo of the show vehicles. I'm confident it will make it's way into the vehicles s---0---0---n

 

[Dark-Fx]

I know we've been down this road before (pardon the pun) but they don't need audible noises in the cab, all they have to do is implement the real-time power guage in the corner of the drive mode video. They had it originally in the UI demo of the show vehicles. I'm confident it will make it's way into the vehicles s---0---0---n

I don't want to have to be looking at the dash when I'm supposed to be paying attention to what's happening outside the vehicle. When you're trying to select a line, it's a terrible time to be looking at the dash. Not sure what your experience is with offroading a car/truck, but imagine looking at your bike computer while you're trying to blast down a trail.

 

[Bee]

I just wasn't going to acknowledge your comment because it was so wrong

I do understand I was more than just setting myself up for that, but for my use case I do think I make a valid case. Dual BEV household that can favor the full BEV and minimize gas miles to road trips only on the 4XE is a pretty compelling use case that I will defend.

Everything else I said on this thread about "want/needing" it to be amazing and still think it will be, is true, which is probably what people are reading and causing them to hold back. I've reported all of my feelings accurately yet you don't see me cancelling my R1 reservation and jumping into a Jeep dealership either.

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