Re: "most mid drive motors, there is some acceleration delay", you have to mean "European mid drive motors (the big 4)" as that would not be necessary on bikes with kill switches built into the brake lever assemblies. The rest of that makes some sense (adjustable).
Five major mid-drive motor manufacturers (Bosch E-Bike, Brose, Yamaha, Shimano, and Mahle) do not think brake-lever kill-switches are necessary, as just stopping the pedalling cuts the power to the motor.
Re: Giant, you're contradicting yourself here. They have kill switches built into the brakes, or they don't. Get your story straight, or help me follow?
Giant uses Yamaha motors. There is no lever-brake kill-switch there either. With "Zero Cadence" present, the Giant e-bike rider is recommended to not set their foot on the pedal before really ready to start the ride. In any case, stopping the pedalling makes the motor power cut-off.
Re: PAS-only, your off a bit. Wheel motion has nothing to do with it. It's based on crank motion, and how far that needs to move is either adjustable by the user, or set by the bike manf. Amount could be near nothing or up to 2 turns. 1/2 turn is pretty normal/reasonable.
I might be wrong here. Anyway, the motor kick-off delay is really noticeable on a PAS-only hub-drive motor e-bike. (The half turn of the cranks actually means the e-bike is already in motion).
"Except the "Zero Cadence" or "zero acceleration delay" "
And how would you suggest that situation be handled if you have no kill switches built in? Seems to me like they (kill switches) might be pretty handy riding a bike set up this way? In fact, this is exactly how my bikes ARE set up, but the kill switches make this a complete non event.
Not to set your foot on the pedal, or rest the foot very lightly there, or, as e-MTBers do, keep both feet on the cranks in horizontal position. As I said, the instant motor engagement is found in e-MTBs to enable technical trail riding. Please watch this video:
See that the instant power delivery is a must on an e-MTB.
An MTBer often remains almost stationary with both feed planted on pedals (the cranks remaining horizontal), and he balances the bike with body balancing. Now, to ride up a rock requires instant power delivery. Same as restarting a steep climb in rough terrain.
"in any case relieving the pressure on the pedal cuts the assistance off. Therefore, neither mid-drive nor PAS-only hub-drive e-bikes need to be equipped with power cut-off brake levers."
This is complete nonsense. Spoken like somebody who has never been on one. I would like to see you climb on a bike with torque sensing, have the motor engage due to your foot applying pressure on the pedal, and you maintain your balance well enough, while having enough wits about you to realize what's happening fast enough to get you foot off the pedal to shut down the power.
Thinking you could sell tickets to that show. There's only one way for that to end....you, and the bike, are both going down.
@AHicks: Do you have issues with understanding simple English? Or never rode a premium mid-drive motor e-bike? I happen to have owned two Specialized e-bikes, one Giant e-MTB, and a Czech PAS-only hub-drive motor e-bike.
No pedalling, no power delivery to the motor. (With some noisy motors, you can
hear the motor has stopped working and got disengaged by the clutch).
You ask
me how to restart the ride uphill without the throttle? Learn riding. I stopped to take the top photo and could restart the ride without issues (Specialized Vado 5.0, 53 lb + a heavy rider + cargo).
You talk the Chinese ware. Ya, you need a brake-lever kill-switch with a throttle-operated e-bike. Only don't tell me the Chinese make premium e-bike motors or e-bikes.