Comments by "Dennis Young" (@dennisyoung4631) on "The Engineers Post" channel.

Bingo. That’s what I thought, too. It also makes implementing a multi-speed transmission much easier, I.e. like the two speeds in a cordless drill, only one or two more gears.
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@geemy9675 no, not three times more efficient. Up to one-third more efficient, of which I have first hand experience. (It was quite shocking to see how big the difference was, in fact - about a hundred and fifty watts less, ~ 350 vs 500.) Again, that one Tesla you spoke of has lots of both motor and battery. Enough motor, you can dispense with the gears. I was thinking of something far more plebeian - something that say, a pensioner/retiree might use, or a non-wealthy commuter - that doesn’t have nearly that much power, and in many cases, a fraction of the top speed. I’m talking something that would be straining to go on the freeway, and would be comfortable at 35 mph /60 Km/h. That’s good enough to get groceries, go to the doctor, visit friends, and do short(er) commutes.
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@geemy9675 that works when you have lots of motor and battery. Having gears usually means less power consumption and improved performance when you don't have huge motors and batteries, e.g. hub (single speed) ebike motors commonly use more power and have less performance than mid-drives. The performance issue can be addressed by going big on the direct-drive motor, but then watts per mile suffers a lot. My experience is mid-drives with gears are both much better on hills and off the line, while using about a third less power compared to a (one speed) hub.
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