[robt57]

Sounds like early SM-EW67A front junction box and a BTR2 battery may have been put together.

Have to use a SM-EW90-A or SM-EW90-B front junction to charge any of the internal batteries I believe. Or bar end ports, forget pn.

Reading that somehow charging thru a shifter port somehow is not anything I am aware of being possible. Trying to imagine the connectivity to try it.

SM-BCR2: Battery charger for SM-BTR2/BT-DN110.

Now I have used the BTR2 internal with the SM-EW67A [test ride] front junction with a fully charged battery. Fully knowing I would have to put it back on the bike with the SM-EW90-A to charge it if I left it in place.