I doubt an insurance company would even bother to check.. UNLESS someone is seriously maimed or worse. Once the lawsuits start flying you can bet your ass they'll be checking to make sure nothing is contrary to the manufacturer's specifications. For that, and many, many other reasons, I would never even consider it.
There's no free rides. There are costs associated with motorcycles. One of those is tires. If you don't want to buck up, then stick with a golf cart.
In NY state, any serious accident with injury will be investigated by the police. So guess what. "A penny wise and a pound foolish".