The piggy back 500Wh range extender is a good idea but it’s given the bikes awkward “weighted forward” looks with a steeper downtube angle, particularly the SDURO models. That gap between the front of the motor and the down tube is going to be a huge crud catcher too... Sorry, but it’s a pass from me.
SDURO:
View attachment 16387
XDURO (with 500Wh range extender):
View attachment 16388
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