Nice rides. as for the questions concerning registration/inspection:
In Washington it has always been considered a moped.
Ten years ago when I first started building and riding these things I researched the RCW's and have continually checked for updates. They are considered mopeds if:
Not more than 50cc, not more than 2 brake horsepower, no faster than 30 M.P.H., and have working pedals.
Otherwise it can be registered as a "motor-driven cycle", or if it is older than 40 years (by frame #'s, they don't look at the engine #) it is consiodered an "Antique Motor-Driven Cycle".
Whizzers fall into the motor-driven cycle category...
Hope this clears things up a bit for Washington State...
I go to the chehalis inspection place, the one up here in Tacoma is a royal pain. The officers in chehalis are very friendly and listen to you about your vehicle, making for a very smooth, easy, and pleasant process.
Rif