well i agree with beau mostly...the law goes down to 14" i believe... it should probably be 24" and below gets off.
"(a) 'Bicycle' also means vehicles that meet the criteria
specified in ORS 801.150 (1) to (4) but that have wheels equal to
or less than 14 inches in diameter."
the difference between the skateboards and skates, and scooters is they aren't considered vehicles for the road a beau stated (at least not in most states) and i don't feel much sympathy for the people who are saying they have 9 bikes but can't afford to pay a small premium for them. If you sold one maybe you could handle the expense.
someone did bring up the good point about low income people. Half the people i see riding in the winter are riding because they can't afford a car and due to their ummm....questionable immigration status would have difficulty getting all the paperwork complete to legally drive one. they certainly might be strained by this measure (moreso than anyone that owns multiple bikes)
I am pretty sure that no bike manufactuer would be dumb enough to use the same S/N from year to year. Obviously bikes that don't see the road are kinda screwed.
SECTION 3. { + If the serial number is illegible or missing
when a bicycle is first registered, the Department of
Transportation shall assign a unique serial number. The
department shall permanently stamp the state-issued serial number
on the bicycle frame or shall permanently affix a metal tag with
the serial number to the bicycle frame. + }
^^^ i could see that being difficult to do to a carbon bike