The problem with mechanical repairs is lack of any spares when the units have to sent back to get a new one.has anyone ever tried to fix these engines, not for the "regular hobby-man) but more specialized craftsmen?
When the Panasonic mid drive units were popular a few years ago that didn't have to happen, so parts from the odd failed units could be used to restore others and many were put back on the road that way, going on to last for years. In addition all the sealed bearings were standard easily available ones.
But with Bosch, Impulse etc., if a gear wheel shreds or other complex part fails, there's no viable solution other than a new motor.
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