There are only two legal and free places to ride dirt bikes in Connecticut. One, a huge state park that enters and exits into several towns and public streets and two states, requires the bike to be street legal and have a MC plate. The other, a sealed off federal dam area, requires at least an ATV plate (AKA: off road plate).
In short, unless you own land, to ride in my state you need a motor vehicle registration of some sort. Which one depends on how the bike came into the country. Street legal or off road only.
My understanding is that you can (possibly do not know for sure) change a registration from street legal to off road but you may not ever be able to change it back. The title would be changed for good. Either way the yearly property tax would the same since it is based on purchase price and not usage. I pay more tax for my Honda CRF100F dirt bike than I do for my Honda CH250 street scooter simply because I paid more for the dirt bike.
For me, street legal would give me two great places to ride. Whether or not I would actually ride the TLR200 to get there is another matter. Both are at least an hour from my home and I'd still need to carry extra gas!