Because of its length and the wheelbase between axles ET22 locomotive performs poorly on tight curves, unlike the older ET21 locomotives, despite the fact that the designers were given the same parameters for minimum curve diameter. Using the ET22 at winding tracks can cause severe damage both to rails and locomotive bogies. This forced several modifications, which are made presently. Such changes are essential, as fewer and fewer ET21 locomotives are in service and ET41 are ineffective on highland tracks due to being overpowered (highland trains length is limited by short station tracks).