Hello DaRSaiNT,
welcome to the forum and the community of E-Odin drivers

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A 50Ah version was available here in Europe at the early days of the motorbike. But "only" 50Ah didn't sell well (due to the limited range), so the 100Ah (now 120Ah & 130Ah) became the default battery.
Except the point with the signal crossing issue, all the weaknesses of the bike that you've mentioned are already known (and a few more

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Hope you've got good tires, because the genuine feiben tires (with which the bikes were delivered here in europe) were a real security risk

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Would be nice to know more about your 6kW/50Ah model. For example: which controller is fitted (votol or fardriver ?) and which speedometer?
The effect that the speedometer sometimes shows a "0" is well known.... but this usually lasts only one or two seconds. It's related to the way the controller communicates with the speedometer (they use a serial communication with a TTL level of 10V, in an enviroment where high currents driving the motor might produce some interference with the communication).
About the language here at the forum: because it's a german site, German obviously is the default language.
But English shouldn't be a problem to post questions and get answers. Most of the users here can deal quite well with English.
As you may have seen, whe have a very big "E-Odin Diskussionsthread", where nearly everything about the bike has been discussed or mentioned.
It might be a good idea to use somthing like google translator to work yourself through that thread

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