True position of a cylinder

True position of a cylinder


I have a measurement result that does not seem correct on true position of a cylinder ("D4.1"). 

CMM Manager indicates a "Y" defect which seems too important to be true unless the cylinder is not perpendicular, which is not the case and on the other hand does not find any drift on the "X" axis although there is some.

To check this value, I created a circle "C" at the entrance of the cylinder and another one at the bottom "CIRCLE 1" and there, the values seem to me correct (defect in "X").

I would like to point out that the true positions for the cylinder and the 2 circles were created with the same reference frame. 

The reference frame is: 
1-plane "FACE-A" (Z axis)
2-line "LINE 1" (X axis)
3-circle "B" (origin)