This should solve the problem, though I imagine the price will be high:
http://www.seed-your-ideas.com/Triebwerk/en/index.html.

It would also make transporting and going through doors and/or up and
down stairs more easy with a SWB 'bent or tadpole trike.

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Tºm Shermªn - 42.435731,-83.985007
I am a vehicular cyclist.