R2 Highway Efficiency Test: 80 MPH vs 70 MPH Changed Everything

[mkhuffman]

Generally agree, the available evidence is still limited, but that is not the same as saying there is no data. Specific-speed efficiency readings, road-trip results, independent testing, EPA figures, ABRP modeling, and aerodynamic comparisons all provide imperfect but useful evidence, which is open to scrutiny, but still worth evaluating rather than dismissing outright.

Is this Ken, or is it an AI bot? Sounds like a AI bot response to me.

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[ksurfier]

Have your flying monkey use his AI checker

 

[Dave Cundiff]

Dave, you are well known and definitely respected in this forum. You are always civil and positive in your engagements. Thank you for being here.

The OP has been here a long time, but in his time here he consistently provides information he claims is factual when it is based on almost nothing substantive. And then to justify his opinions he posts AI content with lots of dubious bullet points and unsubstantiated claims.

I don't mind debating with a human being, but debating with him is debating with an AI bot. He consistently uses that method to respond.

I apologize for getting frustrated, but it's very frustrating and hard not to show it. If his conclusions were based on more than just a 10 minute test, or just weighing a tire, I would appreciate his contributions much more. I'm not the only one who sees what he's doing and gets frustrated by it.

His AI bot actually claims a short drive provides useful data when that just isn't the case. His AI bot claims ABRP is useful input for determining efficiency when is simply not the case. I can continue to refute and debate all the bogus AI bullet points, but it is frustrating to do that. So I won't.

Thanks for your kind words, @mkhuffman.

I haven't engaged with the substance of the arguments (on either side) at this time. The exact R2 mileage/efficiency/range aren't deal-makers or deal-killers for me. I agree that incomplete data, or data limited to a narrow range of circumstances, are much less reliable than what will emerge later.

What I engaged with was the name-calling. All of us are vulnerable to engaging in name-calling. But, in my experience, name-calling eliminates honest discussion -- usually starting with the most capable discussants, who have the highest number of other ways to spend their time.

Any sufficiently opinionated person can be mistaken for a bot. My ability to detect bots isn't very good. I'm not sure if any of us is that good at telling humans from bots anymore.

We can say our truth, with dignity and without excessive repetition.

Healthy communities yield the best discussions and insights. My concern was to preserve the health of the rivianforums.com community if possible. I believe that most of us got back to honest discussion, at least for now. Thank you all for that!

 

[Zathras]

Gen 2 aero cone.

That explains the shape of my neighbor's car. (He's the CEO.)

 

[Husky]

I'm interested in the efficiency at speeds of 35 to 50 mph, since that's the majority of my driving, although I understand that efficiency at highway speeds is of interest since that will determine how often you need to stop to charge on longer trips.

I don't expect the R2 to be great at highway speeds, given it's boxy shape, but I wonder how it compares to my EV6 AWD at lower speeds. In the warmer months the EV6
averages around 4.4 m/kwh, and even 5.0 when I'm driving in areas that are relatively flat. I haven't heard any numbers that high for the R2, but I'm not sure why not, since the new Maximus motors are supposed to be pretty efficient,, and the boxy shape shouldn't hurt too much at 40mph.

 

[blipit]

Yeah!

I think a longer test might be closer to >2.2 MPK

You are getting some flak on here. But your 80mph estimates were spot on.

OOS just got 2.2mpk at 80mph during their 10% challenge.

 

[Apprunner]

You are getting some flak on here. But your 80mph estimates were spot on.

OOS just got 2.2mpk at 80mph during their 10% challenge.

Yeah...a lot of people eating crow on this one

 

[mkhuffman]

You are getting some flak on here. But your 80mph estimates were spot on.

OOS just got 2.2mpk at 80mph during their 10% challenge.

Yeah...a lot of people eating crow on this one

For the record, I never claimed I knew what the efficiency at 80 mph would be. Because I have only a rough guess. My R1T can do 2.5 mi/kWh at an average speed of 75 mph. It is logical to assume the R2 can hit 2.6 at 80.

On the flipside, the OP make claims like he has the answer and the discussion is over. It isn't, but that that is how he rolls.

And I disagree his estimates were "spot on". They were not. They were lower than mine, but one OOS test does not end the debate. Not even close. Which is why I have repeatedly said multiple test are needed.

Not "spot on" with 2.2 mi/kWh at 80 MPH in the OOS test:

Look forward to seeing your results...here's a general idea of what you might expect to see...pretty steep drop off from 63 mph to 82 mph:

MPK	Range	Speed
3.6	315	57.0
3.4	300	60.0
3.3	290	63.0
3.1	275	66.5
3.0	264	67.0
2.9	251	70.0
2.8	250	71.0
2.7	238	74.0
2.6	225	76.5
2.4	212	79.0
2.3	200	82.0

 

[blipit]

For the record, I never claimed I knew what the efficiency at 80 mph would be. Because I have only a rough guess. My R1T can do 2.5 mi/kWh at an average speed of 75 mph. It is logical to assume the R2 can hit 2.6 at 80.

On the flipside, the OP make claims like he has the answer and the discussion is over. It isn't, but that that is how he rolls.

And I disagree his estimates were "spot on". They were not. They were lower than mine, but one OOS test does not end the debate. Not even close. Which is why I have repeatedly said multiple test are needed.

Not "spot on" with 2.2 mi/kWh at 80 MPH in the OOS test:

OOS will be doing a 100%-0% any day now, at constant 70mph. So we will have another metric for efficiency at highway speeds.

 

[Apprunner]

For the record, I never claimed I knew what the efficiency at 80 mph would be. Because I have only a rough guess. My R1T can do 2.5 mi/kWh at an average speed of 75 mph. It is logical to assume the R2 can hit 2.6 at 80.

On the flipside, the OP make claims like he has the answer and the discussion is over. It isn't, but that that is how he rolls.

And I disagree his estimates were "spot on". They were not. They were lower than mine, but one OOS test does not end the debate. Not even close. Which is why I have repeatedly said multiple test are needed.

Not "spot on" with 2.2 mi/kWh at 80 MPH in the OOS test:

Yeah. oOS was even worse than his estimates. He was the closest though and I don’t really expect much better in any other test given OOS actually tested in decent conditions.

 

[mkhuffman]

Yeah. oOS was even worse than his estimates. He was the closest though and I don’t really expect much better in any other test given OOS actually tested in decent conditions.

In my experience, driving at 80 mph but averaging 75 due to slower traffic, with regen, is more efficient than driving 75 mph steady speed with no regen. It makes no logical sense to me why that would be more efficient, but I have experienced it in my Mach-e and R1T.

It just another variable to consider when trying to determine how far you can drive in your R2 or R1. Which is why I keep saying we need multiple tests under various conditions to really know what the average driver can expect.

Which is the point, right? I mean if you can get 3.0 mi/kWh at an average speed of 75 mph in your R2, does it matter what OOS got? I think that is totally possible if driving like I did a couple days ago when I got 2.5 at 75 over 150 miles.

 

[Apprunner]

In my experience, driving at 80 mph but averaging 75 due to slower traffic, with regen, is more efficient than driving 75 mph steady speed with no regen. It makes no logical sense to me why that would be more efficient, but I have experienced it in my Mach-e and R1T.

It just another variable to consider when trying to determine how far you can drive in your R2 or R1. Which is why I keep saying we need multiple tests under various conditions to really know what the average driver can expect.

Which is the point, right? I mean if you can get 3.0 mi/kWh at an average speed of 75 mph in your R2, does it matter what OOS got? I think that is totally possible if driving like I did a couple days ago when I got 2.5 at 75 over 150 miles.

The 80mph is useful for me as I travel up and down California and I’m regularly going 75-90mph on the 5 or 15 highway. Going to Vegas at night is much closer to 90 mph and trust me when I say that the slow lane is easily going 80. Our highway patrol regularly cruise at 80mph in San Diego.

frankly, 2.2 mpk is a bit of a letdown for me. I was thinking 2.5 or a bit higher as the MYP is getting 3.2mpk. It’s a pretty bad number.

 

[ksurfier]

The 80mph is useful for me as I travel up and down California and I’m regularly going 75-90mph on the 5 or 15 highway. Going to Vegas at night is much closer to 90 mph and trust me when I say that the slow lane is easily going 80. Our highway patrol regularly cruise at 80mph in San Diego.

frankly, 2.2 mpk is a bit of a letdown for me. I was thinking 2.5 or a bit higher as the MYP is getting 3.2mpk. It’s a pretty bad number.

I agree 100%. The heart of my argument is that we should not treat the R2 and Model Y as similarly efficient vehicles, because once speeds rise into the 75–80+ mph range, the R2 does not come close to matching the Model Y. Rivian did an excellent job with the original Gen 1 R1 lineup, but beginning around 2025 it appears to have leaned into more favorable EPA test procedures that produce numbers less representative of real highway driving. That is a disservice to buyers who rely on the advertised range, yet merely pointing out the data seems to have set some people’s hair on fire.

 

[shandering]

This difference will be even greater in the winter. Tesla cold weather efficiency is unmatched. Even lucid never really cared about cold weather and wanted good EPA numbers

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