Understanding Tire Sizes for Cars, Trucks and Bikes

I just got a flat tire and I need to replace it with a new one. What size tire
do I need to get? This can be a tricky question, and many of us would just take
our cars into a dealership or repair shop and let them deal with it. But it’s
not as hard as you might think, and now Wolfram|Alpha provides tools to help you
understand tire sizes. More...