Under Montana law you do not have to have liability.
If you have a loan on a MC, however, the bank will require that you carry comprehensive and collision to protect their interest.
There are many other optional coverage options, such as carried contents and custom parts and equipment that can be added.
The uninsured/ under insured and Medical are extremely important in case you or and passenger get insured by an uninsured person.
If the autos, motorcycles or any other lines of Insurance can be written by the same company, the discounts keep adding up.