If you're riding on the street, you're more or less stuck with just paying what they charge. The variables will be deductible, and if you combine other vehicles with your motorcycle coverage. That is about it. Sometimes, if you have a very good relationship with your agent, they will do what they can to work numbers. Also, if you have a loan, you are stuck with their requirements.
In my case, I do not ride the street as I am track only. So I don't need collision and other state requirements. I called my agent and explained to him this is to be treated no different than a dirt bike or ATV and I want the same type of policy. He had to call corporate and figure out what to do as their system kept saying it needed collision for street. But, he got it done and I'm paying comprehensive only due to the bike's use.
