ATTENTION U.S. IFMR RIDERS -- YOU'LL NEED A CANADIAN VEHICLE INSURANCE CARD TO ENTER THE COUNTRY
With various recent changes in border security, Canadian border security agents may ask you to show that you have a Canadian NON-RESIDENT inter-province motor vehicle liability insurance card. If you do not have this card, border security may refuse you entry to Canada no matter what U.S. insurance you have. This applies to both cars and motorcycles.
Most U.S. insurance companies will provide a card indicating Canadian coverage upon request at no cost for the days you are in Canada. It usually takes a few weeks to get the card, but sometimes it can be obtained more quickly. Talk to your agent. S/he may be able to issue a card on the spot.
Also confirm that your U.S. insurance will actually cover you in Canada. Not all do. If yours does not, you can Google several web sites that allow you to purchase coverage just for the days you are in the country.
What about rented vehicles?
If you're flying to Montreal and renting a vehicle (car or motorcycle) in Canada, the rental agreement will generally include Canadian vehicle insurance. However, be aware that it is not possible to cross the U.S.-Canada border in either direction with a rental bike -- a restriction that some IFMR riders have sadly discovered by experience.