I have been seeing a lot of kit tanks mounted on luggage racks behind the seat. I'd go that way. Yes you can do a womens bike, I did a 24" one and it was a lot of fun but it was also small.

I even dropped a twenty inch wheel on the back to make it even lower for me. If you check the bike only section you will see a bit about bikes for an old man (me) there are some simple inexpensive changes we can make to help with the stiff legs and bad balance.

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