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Discussion Starter #3
Tremelune, thank you for your reply. I am really new to thinking about an EV build, so I'm in the information "sponge" phase. Just for the sake of discussion, assuming the supplier was reputable, there were no quality issues, etc., does this kit make sense for a lightweight EV build? I'm thinking something like a steel frame, fiberglass replica vintage Porsche 356 or Cobra build?
2x 8KW motors, 96V?
Thanks again
 

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No
Makes no sense whatsoever - hub motors are OK for a pushbike -

And even at the $2,000 that is a very suspicious deal
 

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Discussion Starter #5
I guess doing some very simple math - 8 KW is about 10.7 horsepower. So, even times two motors, you're still at 21 HP, which is pretty crummy, even by an "economy" standard.

Are there other technical reasons not to use hub motors? If the power were sufficient, or using 4 instead of 2, are they candidates? I'm still having a hard time understanding the fundamental or practical flaws.

Thanks!
 

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The fear to me isn't the specs, it's the fact that there's no way of knowing the true quality of those components. They could arrive at your door and be 1kW or simply not work...and there isn't much recourse.

Unidentifiable electronics from Ali Baba aren't known for their quality.
 

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Main reasons I can think of against hub motors are;

Low power density, increasing the unsprung weight of the vehicle, low operating speed - most EVs even without multiple gears have a single speed reduction. You can get a lot of torque out of a hub motor, but it's still pretty equivalent to a single motor with a reduction gearbox.

Hubs also mean more motors = more controllers = more points of complexity to fail. If you have two hub motors driving your wheels, and one fails - you're as stuck as if you had a conventionally connected motor fail, as youll just be doing tight circles on the road...
 

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While I agree that hub motors are generally unsuitable for cars, I don't think that this is a valid reason:
If you have two hub motors driving your wheels, and one fails - you're as stuck as if you had a conventionally connected motor fail, as youll just be doing tight circles on the road...
If you drive just one wheel in a normal car, it will tend to pull toward the other side, but as long as you are steering it will go where you steer. Motorcycles with sidecars are driven on only one side, and most adult pedal trikes drive only one of the two rear wheels.
 

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Any site showing hub motors is exposing the fact that they don't understand what is required for an electric car
 

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Discussion Starter #11
...
You can check this webpage:
https://shinegle.en.alibaba.com/?spm=a2700.9014153.0.0.36823e5ffturXA
...They sells diferent kind of complete kits, including the programing device for the controller.
These kits look interesting. It seems like a reasonable price for a known good working combination of parts. Except for the battery...

I'm trying to find a "bargain" way to get a reasonable battery pack. I don't need Tesla speed or range, just something enough to keep up with traffic and not run out of juice every mile. Any ideas there?

Thanks!
 

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what was your experience? i am deciding between 3 sellers at the moment
shinegle
foshan uni technology
green motor technology

all from alibaba, i want to convert a 1990 Volkswagen beetle
 

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Discussion Starter #13
@pivux I never pulled the trigger for a variety of reasons. The kits do sort of seem too good to be true. Plus, there has been some good discussion about the flaws (and merits) of hub motors, especially with respect to the weight "under" the suspension rather than "over" the suspension. It's a good argument, but the proof is in the pudding. Whatver kit you go with, please keep us up-to-date. Good luck!
 

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Discussion Starter #14
@pivux, just for the heck of it, I Googled "QSMotor car conversion". it looks like people have done it! Of course, so far, they are not English speakers, so I can't understand what they are saying in the videos (which may be "this piece of [email protected]! Why did I waste my money!", or maybe not.) So, I say DO IT!
 

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@rubinstu if you search that in google, you will see there is as much 1 or 2 videos, and not very clear, it is not the same seeing one video, as knowing the lifetime of those motors (QS company told me through alibaba their motor lasts 3-5 years in harsh conditions and 5-10 years in good streets, therefore, i will go for an AC induction 3 phase motor kit from the previous companies I said, which have been use in Mexico many times, i can give links, but videos are in spanish, i will keep you guys updated!
 
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