Using Cissy's shopping bike (the police took mine). No gear shift, no back-pedal brakes, no helmet (but an iPod). No way to measure speed or distance. Probably around 20km. Took two hours and twenty minutes anyway. Lost at least half an hour in Mita by taking a very wrong turn.

I think of this as a one-time thing, same as climbing Mount Fuji (a wise man has to do it once, but only a fool would do it more than once), but it was actually quite pleasant (well, my legs will offer their opinion on this tomorrow), and I have to do it at least once more to get home tonight -- in darkness.

Update: The ride home also took two hours and twenty minutes, including about ten doing circles in Kameido (almost home) trying to find my bridge across the the river.