[Official Feature] Rivian Drive Systems Decoded: Dual-Motor, Enhanced Dual-Motor and Quad-Motor

[kylealden]

Modern AWD with ABS torque vectoring is very effective and avoids serious downsides of lockers (can't be used on-road, forces all but one wheel to turn at a suboptimal speed, etc.). Is it 100% as good as full lockers for the crawling use cases where lockers shine most?

Probably not. Is it 95+% as good for the overwhelming majority of use cases, including off road? Yeah.

(In fact there are probably scenarios where Dual Motor + ABS will outperform Quad Motor since it can send more power to a given wheel.)

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[johstacy]

This may be an outlier, but the many reports of only getting around 20k per tire is pretty dismal.

I said this in another post but having the Rivian the only maintenance you have on your vehicle is your tires.... So you have to calculate that in to you cost of ownership but you get to remove all the other maintenances

 

[kylealden]

I'm a fan of the quad motor to be honest but I do have a question what is the towing capacity of the dual motor systems?

If you read Rivian's post, they confirm towing capacity is the same across all three systems.

(I imagine the limit here is the frame + brakes, not power.)

 

[johstacy]

Same towing capacity as quad.

wow I wonder how that works you would think you would have more towing power with a quad

 

[Dark-Fx]

wow I wonder how that works you would think you would have more towing power with a quad

It sounds like the limitation is structural versus power. Rivian probably could transplant the R1T quad into an HD frame and have a much higher towing limit without making any other changes.

 

[aAlpine]

Proven by whom? The video Rivian posted looked pretty effective to me. The truck did all of the stuff that's hard for a vehicle with an open diff.

Sure, here's one example:

Toyota's ATRAC system is a many years old (meaning refined) brake traction control system. Certainly better an an open diff, but much more wheel spin and less precise than a true locker. There's a reason the 4runner comes with a locker on the rear axle.

At least one benefit the dual motor Rivian has no need to share torque between the front and rear wheels. It's just disappointing because with lockers the dual motor spec could actually outperform the quad motor in low speed crawling situations (and maybe that's one reason they decided not to implement this, other than cost cutting)

 

[SoCal Rob]

Proven by whom? The video Rivian posted looked pretty effective to me. The truck did all of the stuff that's hard for a vehicle with an open diff.

Some people think that solid axles plus springs plus all locking differentials is the absolute best for off-roading and anything else is worse. That “conventional wisdom” may apply to a dedicated off-road rig.

For those of us who use the vehicles as daily drivers, who want good handling and value good ride quality, I think the conventional wisdom isn’t particularly helpful.

I’ve written enough about it that I won’t repeat myself, but if you’re driving a modern off-road capably SUV the same way you would the solid axle, spring suspension, manual locking differential type then you’ll find it lacking. We’ve taken a modernish LR3 (height adjustable air suspension, independent suspension, some auto locking diffs and beanie based traction control) to places where the conventional wisdom folks couldn’t believe we got… and we got there in comfort both on- and off-road.

 

[Dark-Fx]

Sure, here's one example:

Toyota's ATRAC system is a many years old (meaning refined) brake traction control system. Certainly better an an open diff, but much more wheel spin and less precise than a true locker. There's a reason the 4runner comes with a locker on the rear axle.

At least one benefit the dual motor Rivian has no need to share torque between the front and rear wheels. It's just disappointing because with lockers the dual motor spec could actually outperform the quad motor in low speed crawling situations (and maybe that's one reason they decided not to implement this, other than cost cutting)

Don't forget there is still a huge power/torque difference between the Rivian and traditional ICE vehicles at zero tire RPM.

 

[aAlpine]

Don't forget there is still a huge power/torque difference between the Rivian and traditional ICE vehicles at zero tire RPM.

As a max pack reservation holder, I hope I'm wrong and pleasantly surprised by performance! I think that the video of the R1T crawling up a high grip rock face isn't a great showcase of the capabilities though, so we'll just have to wait for more content.

 

[Madsen203]

Happy to get the 2 motor R1S over the quad. Less to go wrong I’d think. The enhanced mode will still be as quick as most EV on the market and still spank most EV performance oriented vehicles (MYP, MMEGTP)

 

[kurtlikevonnegut]

Most interesting to me with this is the timing of this release. It makes me think they are much closer to starting production of dual motor variants than originally forecasted (start of 2024). I don't know why they would post this if they are still over a year out on production of anything applicable.

 

[Sully151]

Does anyone think they are going to change to the dual motor for the remaining LE Large Pack reservation holders?

I am kind of torn on this. I don’t do crazy off-roaring,but love more range so the Dual Enhanced would be a good fit. Theoretically.

On the flip, the quad motor system uses proven motors and is what I signed up for.

 

[theyoungone]

I think some current shoppers will see $8,000 (as of today, prices subject to change) as a good reason to go for the base dual over quad. Pre-3/1 reservation holders still save money over quad but not as much.

You are correct. $8K is a good chunk of change. I am different in that aspect I guess. I’d rather just save longer or finance a portion of it if I’m only getting 20 more miles out of my battery.

 

[theyoungone]

Good lord what are you doing to those tires?

absolutely nothing that’s the thing. I DON’T have one (yet) but do some reading about the 21s. People usually opt for the 20s or 22s. But what I’ve read about the 21s is a minimum of 10K and an absolute can’t drive anymore MAX of 30k. I’m talking about slick and threadbare at 30. And that’s normal driving. Like people doing their every day driving and seeing insane wear. Which is insane to me. And then the fact that it’s a custom tire. And then to have to replace a whole set for almost 2K twice a year. It’s a hard pass for me.

 

[Inkedsphynx]

Sure, here's one example:

Toyota's ATRAC system is a many years old (meaning refined) brake traction control system. Certainly better an an open diff, but much more wheel spin and less precise than a true locker. There's a reason the 4runner comes with a locker on the rear axle.

At least one benefit the dual motor Rivian has no need to share torque between the front and rear wheels. It's just disappointing because with lockers the dual motor spec could actually outperform the quad motor in low speed crawling situations (and maybe that's one reason they decided not to implement this, other than cost cutting)

This is hardly an apples-to-apples comparison with an R1, given that it's got 4 independent motors at each wheel, each of which puts out about the same torque (at 0 rpm) as that 4Runner does at peak RPM. ATRAC and what Rivian is using aren't even close to the same type of system or software.

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