I love my 18" carbon wheels and wont reduce to 16" non carbon. I accepted the 3S as my option for gears. However, the slopes I climb every morning are too steep, to the point that I broke the gears (sturmey archer needs to improve quality !)
I decided to reduce the gear ratio.
After a lot of ressearch, I went for the outstanding Veercycles’ 72T front belt drive, Ticycles 104 to 130 BCD adapter that handily comes with perfect washers enabling alignment of rear and front drives, 7x 8mm bolts from problem solver (I love these guys!), 2x 18mm M6 aditional bolts and a contitech belt (1304 8M 13mm, actually a 1312 8M 13mm would be even better but it was not distributed where I live). Freewheel is the original Strida.
All this fits nicely together.
Gerar ratio is now reduced by 72/100 and I am a happier strida rider despite a dent in my savings (expensive stuff!)