Seems legal most places. I called the Washington state patrol office near me and they said no problem driving to downtown from my place. Everson to Bellingham airport where I work. The lieutenant said his friend drives his kids to school in his.
From my understanding it's faily rare.
I know we can't here in Oregon except for a couple small city ordinances.
What is it regestered under? Motorcycle or ? I know the Spyder can be here in Oregon under motorcycle, but they don't allow UTV's
Here's their BS reasoning.
"A quad or side-by-side cannot become street legal under current Oregon law
. These vehicles were never intended for on road use. The engine emissions do not meet federal highway emission standards, do not have the proper equipment and cannot be retrofitted with equipment to become street legal."