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Tesla Roadster

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671–680 of 729 posts

Re: Tesla Roadster

#671

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You have been reading too many finance blogs. Their finances are far from a mess, they are just not what finance people like to see. They have cash on hand and a roadmap to execute on. If they don't execute they will go out of business, and they will take my money as an investor with them. I'm OK with that and as long as they continue to have a path to profitability I am all on board. I want to see them burning money…

Exactly. As a small investor in them I fully support them. Even if I lose all my money I know it went to cool research that has benefit the progress of science in a cool way.

I mean, that's fine and dandy, but then you're really just donating your money to "science" and not investing it. Which goes back to the original claim that their finances are a mess.

Re: Tesla Roadster

#672
post #638

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Yep! The tires are actually designed to do that. It really helps to prevent things from snapping by absorbing some of the shock when the cars drop the clutch or let go of the trans brake.

So the tires are acting like torsion springs then?

It increases the footprint of the tire at the start, giving the car more grip. Here is a video: https://youtu.be/-VF0JwxQqcA?t=10m42s

Re: Tesla Roadster

#674

Earlier quoted context omitted.

I'm curious as to why you choose to believe that their was a conspiracy to release a sped up video rather than the fact that the car really is just that quick. Cognitive dissonance? Shorting Tesla stock? It's not like you're mentally deficient or anything so there has to be a logical reason in your mind as to why you ended up thinking this. I would be very keen to know what that is.

I don't think it's altered video. I'm just describing possible things that people could see in that video, which might lead to that conclusion: 1. an odd camera motion; 2. scared spectators jerking; or, 3. altered video. I do, however, think the people downvoting me have significant reading comprehension problems. However, that's a thing they will have to reflect on, internally, and has no bearing on me.

You started off with a claim that the video was sped up (i.e. _altered_). I'm not sure anyone downvoting you has a problem reading.

Re: Tesla Roadster

#676

Earlier quoted context omitted.

> I tune EFI systems on race cars as a hobby, and any car in the 8 second range usually needs to run slicks or drag radials to have enough traction. Right, but you're comparing what is ultimately powered by the good old Karl Benz design from the 1880s, burning dinosaur juice, that has zero torque at zero RPM, needs to shift gears multiple times, and is about as responsive to control inputs as a cow munching on mariju…

A couple of points: 1. A drag car does not start at zero RPM. The engine is probably over 4000 RPM and under load before the race even begins. In fact, many cars have to dial their launch RPM down because it ends up making enough power to lose traction from a dead stop. Look up "trans brake launch" to see what I'm talking about. 2. Your comment actually further confirms my skepticism of the Tesla not being able to ma…

> A drag car does not start at zero RPM.

I own a modern sportbike and I've done enough of quarter mile attempts to understand how the process works in general, even though it's not a 4-wheel vehicle.

The main point here is that the internal combustion engine has a primitive torque profile. You have to keep it in the sweet spot if you want maximum performance. Hence all the stupid tricks you need to play with gear shifts and the clutch and all that junk.

This whole coordinated ballet is unnecessary with electric motors, that's the point that you've missed. At any RPM, including zero, the electric motor is near peak torque. A whole range of complex issues that would otherwise need to be mitigated simply vanish, so you can focus on defeating other obstacles. Understand the difference now?

> If an unresponsive internal combustion engine powered car has trouble, imagine a car capable of shocking the tires even harder.

You're missing the point again. A much more responsive engine such as the electric power plant allows traction control to work much, much more precisely and respond much faster. No inertia from crankshaft assembly and transmission. No clutch. Torque goes from any value to any other value in a small fraction of a second. The feedback loop can operate that much faster, and with greater precision. Internal combustion engines are not even in the same ballpark.

Like I've said, I do own a racing vehicle powered by internal combustion. I am quite fond and proud of it, which is something I believe you understand. But it's game over for this technology. Electric engines are winning by all metrics and in all applications, either sports, or utility, or whatever. It's the end of an era.

Re: Tesla Roadster

#677

Earlier quoted context omitted.

> I tune EFI systems on race cars as a hobby, and any car in the 8 second range usually needs to run slicks or drag radials to have enough traction. Right, but you're comparing what is ultimately powered by the good old Karl Benz design from the 1880s, burning dinosaur juice, that has zero torque at zero RPM, needs to shift gears multiple times, and is about as responsive to control inputs as a cow munching on mariju…

Even if the difference was that drastic, none of that accounts for the fact that tires only have so much friction.

Yeah. Nobody claimed that magic was at work here. Current tire technology has certain limits imposed by physics. But I suspect electric cars can get quite a bit closer to those limits, with a much faster traction control loop.

Re: Tesla Roadster

#678

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Despair not. The new Roadster will likely have some good competition by 2022.

I hope so. I've been waiting for details on the next Roadster for quite a while now, really on the edge of my seat for the price. My plan was to get a Nissan GT-R in 2021 if the Roadster ended up being too expensive. But since it was announced and too expensive, I'm still on the fence. I don't want to spend $120k on a GT-R and feel disappointed that I settled. I'm thinking I'll just have to save money for a couple ye…

Only problem there is, I expect Tesla won't be making very many of these for at least the first few years, so I doubt they'll depreciate much, if at all, on the used market. Could actually sell at a premium, as you see with other hard to buy supercars.

Re: Tesla Roadster

#679

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This isn’t CGI :-) https://mobile.twitter.com/DavidHodge/status/931391188065705...

This video freezes right before the excitement, I can tell because the sound keeps going. I blame a very complex conspiracy.

Had the same issue in Safari, it worked in Chrome though.

Re: Tesla Roadster

#680

Earlier quoted context omitted.

"I don't think torque is constant." The torque is constant for the first 40% of the RPM, something like this: http://image.motorcyclistonline.com/f/30634938/122_0910_03_z... http://www.global-greenhouse-warming.com/images/TeslaTorqueg... The horse power increases gradually as RPM increases.

Interesting. Do they do that on purpose or is it due to how the motor works? It's so flat that It seems like they limit the torque on purpose, perhaps to prevent breaking things. The almost perfect linear decline after the constant part is what I would have expected for an electric motor running with a constant power.

They almost certainly are limiting the torque. Zero rpm torque on these electric motors goes asymptotic since torque is power per change of angle and the angle isn't changing.

Also he specified max torque was 10k newton meters which is absolutely enough to pull a steel driveshaft like taffy. That's triple the torque a semi produces.

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