Ok, track 101
There is metal inside the tracks, they are encased in rubber. There are also cables that run the length of the tracks
This pic shows the rubber deteriorating but you can see the metal that runs across where the sprocket gear engages
Attachment 52719
Here is a cross pic of the track, you can see the cross bar with holes and if you look at the rubber track you can also see holes where the cables run thru. The weird U shaped bracket is what keeps the track running true, the sprockets and the bogie wheels have channels that that bracket runs between.
Attachment 52720