bezier curve loops are twisted I'm trying to make loops for a stunt car racing game. It's easy enough to make a bezier curve that looks like a loop, but once I try filling it with another curve, the results are undesirable.



Where it's supposed to go from being right-side up to up-side down and back to right-side up again, it instead does only a 90 degree twist at the top of the loop and then finishes with something like a 135 degree twist from the starting rotation? Either way, it is not the iconic roller coaster/hot wheels loop that I am looking for. This is my bezier curve, is there something easily identifiable that I am doing incorrectly?
Adjust handle's tilt value

According to a Blender reference manual's page:


  If the “curve path” is 3D, the Tilt value of its control points will be used [...] to twist the “curved” object around it.


See also this page for further explanation, but basically the setting control the direction of the beveled/extruded object along the curve.

You can find the absolute value of the control point tilt in the properties shelf



You can edit the titl value directly there, or tweak it by pressing Ctrl+T shortcut or you can find the operator in the 3D View menu bar-> Curve-> Control points-> Tilt