New Tesla CEO Ze'ev Drori finally speaks
The new CEO and President of Tesla Motors Ze'ev Drori has been pretty quiet since he came on board recently, at least publicly. He did participate with Elon Musk in the recent conference call with customers and he has undoubtedly made his presence felt inside the walls at San Carlos. Now, anyone can hear what Drori has to say: he's just posted his first entry on the Tesla blog picking up where Elon Musk left off last week. Drori gives some further details on the situation with the Roadster's transmission. The one speed unit that will be used for early production cars will mainly impact the acceleration with 0-60 times going from 4 seconds to a still-spritely 5.7 seconds. There's also some discussion about the range of the Roadster. After the recent revelation that an error was made in the test procedure, Drori explains that the dynamometer at the test lab was incorrectly calibrated. After a retest, the official range is 221 miles but real world numbers range from 165 miles in aggressive highway running to 267 miles in lower speed urban commuting.
Gallery: Riding in the Tesla Roadster
[Source: Tesla Motors]
Reader Comments (Page 1 of 1)
Me 10:57AM (12/28/2007)
4 seconds to 5.7 why even bother. That is going from super car territory to normal car. This really upsetting electric motors are known for great low end torque. Some thing is going very wrong at Tesla.
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Darryl 11:10AM (12/28/2007)
The slightly reduced performance will be a temporary thing for early cars and they will be upgraded to the original spec as soon as the upgrade is ready. There is more detail on this in Ze'ev's letter on the Tesla blog.
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Me 11:25AM (12/28/2007)
They decided to ship the car with out a low gear, enabling high speeds. I would have gone the other way shipped the car with only low gear, keeping the 0-60 but limiting the top speed. Human only sense acceleration not speed. Driving the car over 100 mph is illegal almost everywhere, but acceleration is legal, you will get more wow factor out of fast off the line times.
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Mike 11:34AM (12/28/2007)
Me -
I'm not sure you fully understand 0-60 times. 5.7 seconds is not a slow time by any means, and certainly does not qualify as 'normal car', but closer to a performance car. I understand this is far from 'super car' which is how the rest of the vehicle has been designed, but they have promised transmissions upgrades to bring the car to its full designed potential.
On the bright side 40-70 acceleration should still be a kick for the folks that receive the early vehicles.
On the bright side, it may be a good experience to learn to drive the car a bit before having a car that is likely the fastest (acceleration wise) car many of the pre-order people have ever driven.
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Mike 11:36AM (12/28/2007)
Two bright sides today. I think it's obvious I didn't proof that. :)
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Kardax 11:39AM (12/28/2007)
If they shipped with only the low gear, you'd be redlining continuously on the highway.
0-60 and 100+ MPH top speeds are both irrelevant to normal usage, but highway capability is critical for the car to have any practical value.
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Sam Abuelsamid 11:39AM (12/28/2007)
The other aspect to keep in mind is that using only the lower gear would also cut range. It's likely that under mild acceleration at lower speeds, even the two speed would be running in the higher gear. Although most people won't use the top speed, they will be depending on the range.
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Yanquetino 12:09PM (12/28/2007)
A mere 1.7 seconds longer to get the Roadster up to 60 mph? Sheesh...! That's what all these delays have been about?! Then they should've gone with Martin's original preference for the single-speed. I reiterate what I stated in an earlier post:
"It wouldn't surprise me in the least if some --perhaps many-- of the first customers to receive their Roadsters will later decide that they prefer to keep the single-speed transmission. They should have that option, IMHO. Time will tell, I suppose."
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Me 12:20PM (12/28/2007)
-Mike
5.7 seconds is not shabby for a $30K (A Sallen Focus or Doge SRT-4 will both do this for less then $25K) but people are paying a lot more money. It is a good idea to learn to drive with the single speed first. I just wanted this vehicle to come out screaming, you only get one chance to make a first impression. The first impression this car is going to make will be diminished the first time it pulls up next to a mustang a gets left at the line. People will say looks cool but still not a real competitor.
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Mike 12:26PM (12/28/2007)
In actuality, if I owned the car, I would probably keep it in second gear most, if not all of the time. I would be willing to bet that for day to day driving it will be much more comfortable to drive in second where you're not likely to jolt yourself and the occasional passenger around.
The fact remains though, everyone who has pre-ordered has done so to get a car that has been advertised as having a ~4 second 0-60 acceleration. I think slipping on this would change the car from a electric car that shatters the general perception of what an electric car is, to a car that is just neat but not revolutionary. :)
Also, from a design perspective again, if you're hauling around a larger car (like, say, WhiteStar), it would make since to change the final gear ratio and depend on the transmission a bit more to compensate acceleration and still have a normal top speed of ~100ish.
The bottom line is I have a bit of faith that they can get the transmission figured out and deliver the car that folks have been lining up to spend $100k on.
"It wouldn't surprise me in the least if some --perhaps many-- of the first customers to receive their Roadsters will later decide that they prefer to keep the single-speed transmission. They should have that option, IMHO. Time will tell, I suppose."
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Mike 12:34PM (12/28/2007)
Me-
I agree with this completely. The part I didn't agree with is the 'why even bother?' part. The reason to put out cars with a beta transmission is that Tesla is actually selling an electric car that you can get more that 200 miles range and can be driven on the freeway. The short sided part of me sees this as the most important part, but in fact having a car capable of out performing gasoline cars in its price range is the bigger picture here, and likely will be the thing that gets the general public exited about electric cars.
Thanks for putting me in my place a bit. :)
"The first impression this car is going to make will be diminished the first time it pulls up next to a mustang a gets left at the line. People will say looks cool but still not a real competitor."
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Mike 12:41PM (12/28/2007)
Without being too wordy here there is one other thing I'd like to add.
The biggest concern for Tesla motors now should be delivering to their customers.
Because of this I do think it makes more sense to release a beta transmission and get the owner in the driver seat daily. This is what they lined up for.
Disappointment can be a strange thing, sure some will be disappointed that they do not have 100% performance on delivery, but I'm sure they'll be elated that they have their key in their hands.
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Joseph 4:17PM (12/28/2007)
Sam said...
"using only the lower gear would also cut range"
This may very well be true. After all, you did take a ride in the Tesla Roadster. :) But, the first gear is the gear with the regen, so wouldn't first gear be more efficient?
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OhmExcited 1:33PM (12/28/2007)
No disrespect to Mr. Drori, I'm sure he is very capable and goal oriented, but he would be better suited as a vehicle line director. His blog is all business, no humor or inspiration. You should have kept Martin on board as the Bob Lutz of Tesla.
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Sam Abuelsamid 2:31PM (12/28/2007)
Joseph, regen is not dependent on the gear. As long as the wheels can drive the motor, you will get regen. The amount of regen you can get is in part limited by the battery and rate at which in can absorb energy. For most current hybrid and EV batteries today, about .3-.4g is the maximum amound of decel you can get via regen because the battery can't soak up the electrons any faster. With some newer batteries like those from A123 and Altairnano, they can safely be charged faster so more regen may be possible.
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Joseph 4:37PM (12/28/2007)
I know they say not to bite the that feeds you, but I gotta correct you Sam.
If you go to the FAQ, and select, "Why does the Tesla Raodster have a two-speed transmission?" it will say,
".....First gear has strong "regenerative braking" that recharges the battery during deceleration and feels like engine braking in low gear on other sports cars. Second gear has less regenerative braking........"
First gear provides more regen, but I guess it is possible to have higher range in second gear due to its taller gearing.
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Sam Abuelsamid 4:59PM (12/28/2007)
I suspect the regenerative braking in first gear is probably tuned to give that feeling of extra decel, because as I said the maximum regen is generally limited by the battery charge rate. We'll probably find that with the single speed transmission the regen at lower speeds will probably be just as strong. All of these parameters are controlled in software and within certain limits there is a lot latitude for getting whatever feel you want.
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Kardax 5:01PM (12/28/2007)
The regen level is configured in the Roadster's firmware. They could offer strong regen in both gears, if they wanted, but they're pursuing a certain "feel".
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jake 6:03PM (12/28/2007)
@Kardax
I think you are right, as they mentioned in their configuration for the 2 speed they wanted to simulate engine braking, so they set their firmware that way.
@Me
Yeah 5.7 seconds is quite slow for a supercar of it's price, though it is still in the performance car territory, but this is a temporary transmission.
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