The motor similarity isn't the issue David, it's the operating regions as I've explained above.
An electric motor of the types used on e-bikes has well understood characteristics.
They start from no revs with minimum power, maximum torque and maximum inefficiency.
As the revs rise, the power gradually increases and the torque gradually decreases until the the point where they cross as shown when plotted, at around half torque and nearing full power, but the inefficiency remains very high during that period.
That point is typically around 8 to 9 mph on a 15.5 mph e-bike, more rarely at extremes of 7 to 10 mph.
From that speed point the power rises and the efficiency gradually starts to rise until it reaches it's maximum, typically around 13.5 mph on a 15.5 mph bike, falling fractionally thereafter.
It follows that when a hub motor bike is running at around it's optimum power/torque compromise and hill climbing speed of around 8/9 mph, it's at around half revs and inefficiency is high with much more current consumed than when at the maximum efficiency region of around cruising speed on the flat.
Since a crank drive motor drives through the gears, falling road speed due to conditions doesn't necessarily mean motor revs drop into the inefficient regions, a lower gear chosen allowing the motor to carry on spinning in the maximum efficiency region at all times.
To get emotive e-bike issues out of the picture, there is a valid comparison with cars here.
With a car having a very large engine and manual gearbox, one can neglect to change down for a hill and punch up it in a high gear on sheer power alone. This is the hub motor equivalent, power substitutng for efficiency in those circumstances.
Try that with a small engine car and it will promptly stall, changing down is absolutely necessary. Doing that enables the smaller engine to do the job less wastefully than the big fixed gear engine.
This is not just theory. I know from experience that at my age and fitness I would struggle to get near 50 miles on your 518 Wh battery on a moderate route in my area, more like 40 miles on a good day, but I can reach 50 miles on a 260 Wh Panasonic battery.
Even when using power all the time and high power mode freely on hills, on the Panasonic unit I could repeatedly do 35 miles with the 260 Wh battery on the hilliest routes. That's the equivalent of 70 miles on yours which for me is out of the question with the hills round here. In fact some of them I can't climb at all on your bike type, but I can climb any of them with the Panasonic unit, even 1 in 3 with it's far lower peak maximum power.
The difference in both range and ability is the efficiency of driving through the gears.
All that said, I love hub motor bikes as well and there's much to be said for their simplicity, their more abundant power and the often greater flexibility on how the power is used. And there are many territorial circumstances where the balance of advantages is in their favour.
I fully understand that you prefer to use those and have that set of advantages and I respect that valid choice. Long may all customers have such a good choice of systems on high quality e-bikes, try both and choose to suit themselves.
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