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reycharles | 1 year ago

In an electric car? Really? I don't know too much about electric cars, but it's my impression that gears and transmissions are completely unnecessary in an electric car. Please correct me if I am wrong.

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rightbyte|1 year ago

There is usually a speed reduction from the motor towards the wheels.

Direct drive or wheel hub motors are uncommon.

The difference is that one fixed gear ratio is usually good enough.

Heavier vehicles more or less need multiple gear ratios for EV drivetrains too.

orra|1 year ago

Precisely. Electric cars almost universally have one fixed gear, with the engine smoothly providing variable torque.

jaredhallen|1 year ago

This is a nitpick for sure, but as I understand it, electric motors provide pretty much constant torque throughout their operating range, which is one of their benefits. It's the speed of the motor that varies, and consequently the power, which is a function of torque times speed.

ZeroGravitas|1 year ago

I believe multi-motor EVs sometimes tune the motors to different uses, switching between one or the other (or both) to provide a similar effect as a gear shift.

serf|1 year ago

this is a cost savings feature that was enabled by electric motor torque at low speed and the consumer's willingness to sacrifice high speed operation to focus on city driving.

electric motors hugely benefit from gearboxes, they're not used as a means to simplify and encheapen.