Tesla 67 Volt Vs 84 Volt Performance Differences?

[Esash]

Anybody know for sure of the performance differences, if both Teslas have the 1900 watt motor?

I've read in other threads that the 67 volt version of any wheel would likely have MORE torque, and the 84 volt version would have higher speed but probably less torque.

Thanks in advance. 680 wh 67 volt version of Tesla goes for $999 on Gotway USA, seems like a nice deal if there is more torque anyway.

[Hunka Hunka Burning Love]

I think the only 67 to 84 volt comparison that I've seen is @Marty Backe's empirical findings between his ACMs.  He mentioned it was quite noticeable.

Moving from my 55 volt Ninebot to the Tesla I honestly haven't noticed much difference except that the Tesla can go oh so much faster.    Of course, I don't accelerate like a mad man on either one, and I only have 50 km on the Tesla  as compared to the 1200 km on my Ninebot.  (It's eternal winter here dammit) Climbing hills is easier with less slow down, but again I haven't pushed my Tesla very hard.  I got my 1024 wh Tesla from AliEx for $1300 delivered.

I bet either 67 or 84 volt would be fine depending on your riding style and where you want to ride.  I can climb pretty steep hills on my Ninebot but slowly.

[Esash]

Thanks.

" @Marty Backe's empirical findings between his ACMs.  He mentioned it was quite noticeable."

I'll try to find that thread to find out what was noticeable.

I'm a torque junkie, not a speed junkie, so I guess I'm lucky. I'd love to be able to "fly" up very very steep hills at 10 mph or more.  

[Hunka Hunka Burning Love]

 

[Marty Backe]

3 hours ago, Scouts Honor said:

Anybody know for sure of the performance differences, if both Teslas have the 1900 watt motor?

I've read in other threads that the 67 volt version of any wheel would likely have MORE torque, and the 84 volt version would have higher speed but probably less torque.

Thanks in advance. 680 wh 67 volt version of Tesla goes for $999 on Gotway USA, seems like a nice deal if there is more torque anyway.

I didn't go any scientific experiments, but I can say that when I switched from my 67-volt ACM to the 84-volt ACM there was a noticeable jump in raw power (acceleration, speed, etc.). The same also when I upgraded my 67-volt MSuper to the 84-MSuper.

So I would bet that the 67-volt version of the Tesla would be slightly underwhelming. Than again, if you have nothing to compare it against, maybe you would be happy.

[johrhoj]

Given the same current (depending on the batteries), a higher voltage equals to higher power. That is a just physics law: Power equals to Voltage times Current.

Whether all that power is wielded and put to the road. is an entirely different matter.
I am inclined to say: off course it is. Why else did the wheelmakers feel the need to go to higher voltages in the first place?

Also, wheels go faster that 3 years ago. In going faster, you need more power (you are fighting the extra air friction).

Much comes down to the motor in the wheel. Does it convert this extra (sustained or peak) electrical power to better accelleration and safer high speeds? I hope someone on the forum can answer this question.

[meepmeepmayer]

I'm no expert, but this is how the theory works:

• voltage ~ top speed
• current ~ torque
• outgoing power (power produced by the wheel) = voltage * current

84V/67.2V = 1.25, so 25% difference.

Current is the same OR better on 84V. As it depends on the number of serial cell blocks, which is either the same OR more for the potentially bigger 84V batteries.

So everything says the 84V is up to 25% better than the 67.2V in all respects. The 67V certainly won't have better torque.

@Marty Backe found big differences between the 67.2V ACM and msuper V3 and wouldn't want to go back.

Buy 84V or not at all There's even battery sizes close to most 67.2V ones that are 84V, so really no reason to buy a 67V Tesla.

The motor power of 1900W (nominal) is just a random number they get from their supplier. @Jason McNeil even said that all such motors would probably overheat if going at nominal for long enough (which defeats the definition of nominal). All you can say, if that number is bigger, the wheel is going to feel more powerful.

You can do the math, 4 parallel packs max (for the Tesla) * 10A reliable max per cell (serial block) * 84V max voltage = 3360W, which is well within the max power of a 1900W nominal motor (I'd guess it at 3500W).

The thinking of having to divide power between voltage and current is wrong, as you don't get more current by lowering the voltage. Motor power is outgoing power, not some fixed incoming power budget. All the motor power tells you is whether the motor can make use of what the wheel provides (in this case, yep, but as said, these numbers are a big part fantasy anyways).

More voltage = better. More current = better. The only case where low voltage would help if this would allow for more parallel battery packs (with the same battery capacity compared to a higher voltage), which would allow a higher max current. You could design a high torque wheel like this (maybe the Z is?). But for existing wheels, that isn't the case, as you don't get more parallel packs with lower voltages, just smaller batteries (also, the Gotway electronics would fry way below the interesting current numbers).

[Esash]

1 hour ago, meepmeepmayer said:

I'm no expert, but this is how the theory works:

• voltage ~ top speed
• current ~ torque
• outgoing power (power produced by the wheel) = voltage * current

84V/67.2V = 1.25, so 25% difference.

Current is the same OR better on 84V. As it depends on the number of serial cell blocks, which is either the same OR more for the potentially bigger 84V batteries.

So everything says the 84V is up to 25% better than the 67.2V in all respects. The 67V certainly won't have better torque.

@Marty Backe found big differences between the 67.2V ACM and msuper V3 and wouldn't want to go back.

Buy 84V or not at all There's even battery sizes close to most 67.2V ones that are 84V, so really no reason to buy a 67V Tesla.

The motor power of 1900W (nominal) is just a random number they get from their supplier. @Jason McNeil even said that all such motors would probably overheat if going at nominal for long enough (which defeats the definition of nominal). All you can say, if that number is bigger, the wheel is going to feel more powerful.

You can do the math, 4 parallel packs max (for the Tesla) * 10A reliable max per cell (serial block) * 84V max voltage = 3360W, which is well within the max power of a 1900W nominal motor (I'd guess it at 3500W).

The thinking of having to divide power between voltage and current is wrong, as you don't get more current by lowering the voltage. Motor power is outgoing power, not some fixed incoming power budget. All the motor power tells you is whether the motor can make use of what the wheel provides (in this case, yep, but as said, these numbers are a big part fantasy anyways).

More voltage = better. More current = better. The only case where low voltage would help if this would allow for more parallel battery packs (with the same battery capacity compared to a higher voltage), which would allow a higher max current. You could design a high torque wheel like this (maybe the Z is?). But for existing wheels, that isn't the case, as you don't get more parallel packs with lower voltages, just smaller batteries (also, the Gotway electronics would fry way below the interesting current numbers).

Thanks a lot Meep, makes sense of course.

[meepmeepmayer]

Just don't buy a 67V Tesla

[GQS]

The only thing I notice going from the 84v to a lower voltage wheel is that the brakes are not as strong going down a steep hill.  I live in SF and there are a lot of hills here, always scares me when switching to a lower voltage gotway when decending a hill after riding a 84v wheel.