Today again I have a puzzle. This one is not a typical math puzzle. You should use your common sense to answer this simple puzzle. Here we go......

Two identical trains, at the equator start travelling round the world in opposite directions. They start together, run at the same speed and are on different tracks.
Which train will wear out its wheel treads first?

You can post your answers in the comments section.

Update
The train travelling against the spin of the earth will wear its wheel more quickly, as the centrifugal force is less in this train.