I agree with James and Ian about the past Japanese record, and I've remarked a number of time in here that China will probably follow the same course and one day be the envy of others for it's quality products. I do think it will take rather longer than Japan did though.
As they say also, hub motors will not disappear. As I describe in detail in my article on Drive Through Gears in the Technical section of this site, hub motors are more efficient for the majority of e-cycling, and in flatter areas, more efficient all the time. They also tend to be inherently faster at present.
On the Derby Cycles Kalkhoff delivery issue, it's only fair to look at the background. Only a short while ago Derby were a wholly owned subsidiary of Raleigh UK, they produced in much smaller numbers and they'd never made an electric assist bike.
In a very short time they've structured an independent company, produced a number of very good designs, built up production to much higher levels and now made electric versions. In doing the latter they will have looked at how others fared with the Panasonic based designs, seen the tiny sales of BikeTech et al, and the decline and termination of Giant's Lafree series, and would have expected a gentle level of sales in entering that market, and probably wanted that in order to learn.
What has happened has clearly been anything but, and with Panasonic equally unable to respond instantly as well, for the reasons I've previously given and now supported by Erik from his knowledge, delays were inevitable.
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