An apparatus for heating plastic preforms includes a first transport device that transports the plastic preforms in a separated manner, wherein said first transport device has a plurality of recesses for receiving the plastic preforms, and a second transport device that takes over the plastic preforms transported by the first transport device and transports the plastic preforms along a predetermined transport path. The apparatus has at least one sensor device that detects at least one measured value that is characteristic of at least one of the two drive devices, and a control device that is designed to control the drive device for moving the holding elements as a function of this characteristic measured value.