Each chapter of the Wisconsin statutes begins with a section defining terms. The terms defined in this section are only for use in the chapter they were defined in. That's why chapter 194 and 340 have their own definitions for "motor vehicle". Where chapter 194 clearly states that a motor bicycle isn't a "motor vehicle," this definition only applies to chapter 194. "Motor Vehicle" must be redefined if used in other chapters-- that is why it is also defined in chapter 344. If you were to go to court, you could not use the definition of "motor vehicle" from chapter 194 to apply to a statute from chapter 344. Statute 344.62 is the one that states that all "motor vehicles" need insurance, and this statute would use the definition from chapter 344, which I posted above.
Not trying to spark an argument or patronize you, just explaining how we came to this conclusion These statutes are hard to understand and I didn't figure this all out myself.
I don't have experience in the WI legal system so I consulted some acquaintances in the legal system and they agree with our conclusion that, under the current wording of 344.62 and 344.01, a motor bicycle is required to have insurance in Wisconsin.
I created a separate thread for this:
Wisconsin Insurance Dilemma. I would appreciate any debate over whether or not it is legal staying in this thread, since that is the purpose of this thread. But ideas about what to do about the illegality could go in my new thread, so this one could stay focused on the discussion of what is and isn't legal.