Today was the first time I used the new Bike Friday Tikit to get to work (12.5 mi).
I wasn't sure how it would handle some of the very rough pavement on Queens Quay and
the transitions from MUP to road and back, and streetcar tracks. My now-departed 20" folder would deliver sharp kicks through the handlebars and the seat. The big Surly LHT would also transmit the bumps nicely, though not as dramatically. I was very pleased the Tikit was the least dramatic, absorbing the bumps the best. Pehaps it's the flex in the frame, especially the long stem and the seat post (well, the seat post does have Thudbuster, but that wouldn't affect the feel through the handlebars). I'm still on high alert for deeper potholes and try not to attack bigger bumps with too much gusto, but the comfortable ride is great.
The Tikit has 1.35" Marathon Plus inflated to 80 psi (max about 90). The Surly has 1.5" Marathon Racer inflated to about 80 psi, as well. The 20" Dahon was using 1.75" Marathon Plus inflated to about 75 psi.