Would it be possible to upgrade a single-speed Strida to 2-3 speeds?
I know there is a Strida model with 3 speeds but the frame is different with respect to the one of a single speed. In particular, the 3-speeds model has a bottom bracket shell suitable to fit a Sturmey Archer KS3 (https://stridacanada.ca/product/sturmey-archer-ks3/).
Do there exist commercially available alternatives to fit in the bottom bracket sheel of a single speed?
Someone did it already, but they are unreachable. This is the post (in italian): http://stridaroma.it/it/works/kit-upgrade-2-speed/. This is the google translate version. If only I could de-focus this picture!
This is a closeup of the bottom bracket in place and the frame of a single-speed Strida.