WW2 is probably one of the biggest factors for the scarcity of pre 1930 bikes.
during the scrap metal drives, I'm sure many guys got talked into giving up that old bike under the scornful looks of their wives and being scolded into being 'patriotic' when the wives probably were just using it as an excuse to get that old junk out of the garage.
and now, here I am, riding a jap bike across the US
the shame....the shame.....
oh, and the alternator on the 101 is off a geo. a jap/GM product.