Why are two slimmer wheels paired on each side of the axle in buses and container carrying vehicles, instead of a single large broader wheel?

Question

Why are two slimmer wheels paired on each side of the axle in buses and container carrying vehicles, instead of a single large broader wheel?

In: Engineering

Answer 1

There is actually a type of tire called a ‘Super Single’ that’s just a very wide single tire instead of two thinner tires. With the super single there’s actually less overall tire width than two thinner tires resulting in slightly better fuel mileage. The combination is also lighter than duals resulting in a higher cargo capacity. Downside is if you blow you you can’t limp off the road and they aren’t great in snow or mud.