Duty is basically just the Canadian taxes I believe. But call the Canadian Border Services Agency and ask if you want to be sure. Toll free: 1-800-461-9999
^^ Thanks for the tips. Did you find a large cost savings in doing so?Motorcycle tires are not considered a "part". However, motorcycle tires are zero duty, regardless of where they are made. If you are so inclined, check page 40-12 on this document.
You pay GST and PST at the border if you don't have any exemptions.
I brought over a set of Michellins and a set of Bridgestones, and no duty was charged.