Everday Canadian spelling can be pretty flexible. Sometimes it's American, sometimes it's English. One notable exception is when it comes to vehicle tires. Note the "I" instead of "Y". I put this down to the preference for US terms when discussing vehicles. Mention of a car bonnet or a boot can often result in a blank look. It's hood or trunk. Imagine my surprise when I came across a British dictionary that preferred tire to tyre. The Chambers Twentieth Century Dictionary was compiled in the dying years of the 19th Century for use in the coming 20th Century. At the time there were not many motor vehicles around. But the iron band around wooden wagon wheels was known as a tire. Obviously, at some point the Y-folk triumphed in Britain.