I am currently building an express train that runs like a metro system through the server. So that the different cities can be accessed more efficiently. However in certain cases the carts stop at a point and bounce back e.g. they go up a ramp and are about to enter the black tunnel and they suddenly bounce back and head the other direction. Any ideas? Can anyone help me with this? EDIT by Moderator: merged posts, please use the edit button instead of double posting.