Elon Musk Tweets Then Deletes: 85D Actually Has Higher Range Than Model S 85


Elon Musk Tweets On Model S P85D Efficiency

Elon Musk Tweets On Model S P85D Efficiency

There’s apparently enough confusion surrounding the range of the Tesla Model S P85D that Elon Musk took to Twitter to try to iron out some of the details, saying it will closely match the P85+.

Software To Idle 2nd Motor Will Maximize Efficiency

Software To Idle 2nd Motor To Maximize Efficiency Coming

As it turns out, the 85D and P85D’s performance tires sap range by 3% to 5%.  As Musk claims, if the P85D had the same tires as the Model P85+, then the dual-motor version would actually have more range.

Additionally, Musk adds that there’s a software update in the works to improve the efficiency of the P85D.  When that software update gets pushed through, range of the P85D will “closely match” the no-longer-available P85+.  The P85+ had a slight range advantage (~3%) over the P85 due to the use of Michelin tires, as opposed to the Continentals on the P85.

All good, but here is the thing – these tweets were both removed over the weekend.  Luckily, we happened to screen shot them.

Naturally, speculation abounds if it was the EPA (who didn’t appreciate the disclosure conflict with the published numbers) or possibly the SEC (who sometimes aren’t keen with Twitter being used to break official announcements).  Conversely, it could also be internal, perhaps Mr. Musk’s legal/corporate handlers felt the tweets shouldn’t be aired, or possibly the company’s engineers were not confident with the claims.  Then again, there could be some other unknown reason.

Whatever the reason, taking to Twitter to break news on a product then deleting it later is probably not the ideal sequence of events.

Minor Details Make All The Difference, According to Musk

Minor Details Make All The Difference, According to Musk

Categories: Tesla

Tags: , ,

Leave a Reply

29 Comments on "Elon Musk Tweets Then Deletes: 85D Actually Has Higher Range Than Model S 85"

newest oldest most voted

I don’t think the Falcon Wings were the real hurdle for the Model X delays. But the EPA downgrading range numbers isn’t helping consumers. Perhaps, that was intentional?

The drivetrain of the “Model S P85D” is also essentially, the same for Model X. And it’s clear that work continues to be refined in public now.

Other refinements could be Model X specific, since it’s tow rated. Suspension programming might also be tweaked / synced for hauling heavier loads in the rear, to keep the car level to maintain max aero, etc.. “AutoHaul” could present some interesting vehicle specific programing challenges for the Model X, to make towing safer, easier and more efficient.

SMH, did you post this in the wrong forum?

Never mind! I just re-read your post and it makes sense now. That’s what happens when you wake up at 3 am! XD

My fault…

The second paragraph should have been the first. That’s what I get for posting at 3am.


No worries. 🙂

460 km range at 105 km/h
515 kW motor power
165 kW front, 350 kW rear
3.4 seconds 0-100 km/h
250 km/h top speed

I’m sorry to see the 65D go.
Must be demand related.

I think you meant the 60D but I agree. As I recall, it was demand related. The 60 already sees relatively low volume sales and I don’t think Tesla could justify the cost/benefit ratio of a 60D.

to both, I ordered the day the 60D was announced & available to order (discarding my X order). Order cancelled two days later when the 60D was cancelled for lack of interest. Reported here in response to loaner discounts as that was what I was offered at cancellation.

Elon will make a 60, but he really doesn’t want to, and the included options in the 85 don’t give much advantage, cost-wise.

By the time I was done I was in for $78k and the s85 loaner offer with -those- options and 6k mi was less.

So wait, when they cancelled your 60D order, they gave you an S85 as a loaner? Is that a “here, try this instead and then put in a different order?”

It’s good to see the incremental improvements TESLA, Chevy Volt and the Nissan Leaf, are continually making. Gives you faith they won’t abandon the vehicle.

( Listening FORD? )

I doubt Mr. Musk employs anyone that he considers to be his “handler”.

The thing that confuse me was that, initially, he said the 4wd would get better mileage than the 2wd and I could never figure out why.

Now he says it gets worse mileage. Perhaps due to the ‘blended charging’ figure, but such comments I would think make prospective customers put their checkbook back in the drawer until things are fully clarified, which doesn’t appear to be happening anytime soon.

They could just make an honest ‘apples to apples’ comparison between the 2wd and 4wd, but that hasn’t happened to date afaiknow.

The front motor would possibly allow better regen in the city, but as for why it would get better highway efficiency (as the EPA numbers show):
1) 85D uses two smaller motors instead of one big one, which supposedly gives better efficiency.
2) all the 4WD cars have twice the copper wiring / inverters to the motor which may reduce resistive losses.

1). All other things being equal, larger induction motors have higher efficiency.

2). A given AC motor is quite efficient over a wide speed range, especially when not exceeding its ‘base’ speed, which in these cars I’d say would be around 60 mph.. But that’s just a guess, and moot anyway since the motors are not designed to operate on a fixed frequency. But induction motors (the only kind Tesla uses to date) are not quite as efficient as more modern designs. The difference in efficiency between motor types isn’t sufficient to explain the wider difference in mileage; especially when both cars have the same motor type anyway.

Its more like “Now you say this but then you said that”. As the comments a few posts down seem to also indicate.

I thought the rear motor on the 85D was the same as used in the 85.

The front motor in the D is indeed smaller than the rear motor, though.

The common explanation is motors have an efficiency range. As an example, if the front motor was ‘geared’ for highway efficiency then it would do most the work while on your road trip (highway) driving.

Tesla was careful to qualify all the range claims, at a steady speed. They never said general “mileage” was going to be better. It was all about highway range “..at 65”, “..at 55”, etc. The announcement was not that the car’s EPA AER, or its MPGe’s would be better. At least, that was my take-away. It was for a (theoretical?) steady state speed.

Whether Cty, or Hwy, rating, EPA’s drive cycles since 2008 have had much more stop and go. Nothing like a pure 65mph run.

I’m sure a few P85 traders are pretty bummed, right now. For all its fun, the P85D delivers not much more than 2 miles per kwh, in normal driving. Need patch….quick.

It gets “worse” mileage because it has more power available

but also gets better mileage if you drive conservatively, which will be very hard to do having all that power at foot

If you look at the TMC thread that discusses this, a bunch of other unrelated tweets also got deleted (for example the one about battery upgrades coming to the Model S and also a tweet about details on the Roadster upgrades coming out).

So it appears the deletion of tweets was a general thing and not directly related to the specific content of these two particular tweets. So the theory that this is SEC frowning on using tweets to make announcements has the most credibility so far. Supposedly Tesla needs to alert shareholders first that this is an official channel for announcements before they are allowed to do that (and Tesla didn’t as far as people can tell).

Maybe this will lead to a new quip. The condition know as ‘Musk Mouth’: The inability to keep ones mouth shut. I wonder if it will get the same traction as my ‘Midas Musk’ appellation.

Tesla hasn’t confirmed the “80% and 100%” theory many carry around. The regular drive cycle efficiency of the P85D looks to fall short of its reduced rating, of 242 miles. So, that would go against it ever performing on par with the range of the S85.

Of course, Tesla is working on the more efficient mode, and are expected to patch it to the P85D’s as an update.

Beyond all the EPA shenanigans, a bigger miss-statement seems to be that the P85D was capable of “285 miles, at 65mph”, as sold initially during the announcement. There are screen-shots of this, too. People are testing out, in ~60 degree temps and warmer, and falling nearly 50 miles short of this claim. Hard to believe software will close that gap.

Tisk, tisk, Tesla.

Regardless of rated range the EPA stickers (images found online) say:
P85 88 City 90 Hwy 89 Comb MPGe
P85D 86 City 94 Hwy 89 Comb MPGe
Therefore AWD is worse in City, better on Highway and a wash for combined driving.

After this I can’t really see them releasing a 60 kWh Model X. It would most likely get a rating under 200 miles.

It’s kind of strange seeing the range going down further and further when you would expect it to go up. It seems like a 300 mile Model S/X is not coming anytime soon.

Yes. Due to the added inefficiencies of Model X, I would fully expect a bump in battery size as an option, especially if you’re towing large, heavy things behind you…

Since the platforms are shared, I see no reason why a larger pack size would not also be offered for MS. *shrugs*

*** just released *** December 30, 2014
Driving Range for the Model S Family
By JB Straubel, Chief Technical Officer

Footnote: Values for 85D and P85D are pending final confirmation from the EPA and new dual motor torque sleep control software available by the end of January 2015

Quote: “Despite this aerodynamic challenge, highway cruising is where the unique benefit of the dual motor cars, to torque sleep one of the drive units when not in use, is most apparent. Much like a modern computer that can actually sleep in between keystrokes, the dual motor Model S will quickly torque sleep a drive unit when torque is not needed and instantly wake it up as the accelerator is pressed to command more torque. It continues spinning while asleep and the digital torque wake up is so fast that the driver can’t perceive it. It is far superior to the slow and awkward engine startup on stop-start hybrid vehicles.

The software update to implement torque sleep will be downloaded to the dual motor fleet by the end of January 2015 and will substantially improve the range of dual motor vehicles by roughly 10%. All tables and graphs in this paper are shown including the benefits of torque sleep.”

Quote: “It is also worth noting that all new tires have a break in period for the first ~1,000 miles where the total vehicle efficiency is reduced by up to 5%. This can surprise (negatively) new owners or customers who have just changed their tires but will quickly improve back to a normal baseline.”