alt Hacker NewsMotorcycles I could imagine.
Do e-bikes really need significantly more power than they have? They already run arguably dangerously fast for their application. Is efficiency not the primary target there?
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While more power may not make sense, less weight is an easy way to get more efficiency. And if you can keep the same power at a lower weight, that's a win.
Hmm. I am NOT an expert (though I ride and have owned 3 traditional motorcycles). IIUC, reducing unsprung weight is really crucial for handling -- which is why so-called "inverted" forks / front shock absorbers became basically the standard.
The motor to battery weight ratio on e-bike is much more than for cars. Having a lighter motor would improve the efficiency.
They don’t need this motor, but if it can be scaled down… at over 10kW/kg sustained, one could wish/hope to get 200W at 50g (disclaimer: I have no idea how this scales with size). Combine that with 1kg of a 600Wh/kg battery (https://news.ycombinator.com/item?id=45797452. Again, I have no idea how realistic that is), and you have a bicycle that’s only a little heavier than a non-electric one, but gives you a boost for 3 hours (more if you use it sparingly. If you’re cycling at leisure, 100W already is a lot of power)
Yes, all else equal, we want lighter motors in vehicles.
I'm always interested to hear about the latest in lighter and possibly more powerful and torque-y e-bike motors.
If engine can be produced cheaply, can it be limited "in software"? It's like saying people shouldn't use Rasberry Pi to blink an LED.
e-bikes don't necessarily need more power but they could benefit from a smaller and lighter motor. If it becomes small enough to "disappear" in the pedal assembly for example, it would allow more design/parts commonality with normal bikes and fit more people's aesthetic criteria.
The lower weight would be definitely welcome, my ebike is comically heavy compared to a normal one and sometimes I have to carry it up flights of stairs (some German railway overpasses, grr).
Also in scooters it could fit in the wheel (since the wheel is tiny and has to spin quite quickly - no reduction gear needed vs a bike with 26-28" rims) allowing a simpler design and cost savings. But maybe in scooters they're already using in-wheel motors, I'm a bit ignorant there.