In order to change the track width at full speed the normal scanning device can change the distance between the two scanning wheels (1) (Fig. 4).

If a synchrotrain vehicle with a standard active scanning system (1)  approaches the end of a track width and reaches the area of track points (5 Fig. 4) then it will lower the right or left scanning device (2, 7). After that the scanning device (1) will be raised. Now, for example, the right scanning device (2) is active. With the wide carrying wheels (3 Fig. 5 and 6) every vehicle can operate on both track widths (4, 6).

Now the distance between both wheels of the scanning system (1) in the raised state will be adjusted to the new track width and the scanning device will be lowered again. Thereafter the scanning device (2) will be raised and the vehicle operates like normal vehicles of this track width again.