The flatter sections of the line have a maximum speed of 160 km/h. But while the route has seen a great deal of investment over the last 30 years, MÁV reduced the maximum permitted speed on the hilly section between Bicske (35 km west of Budapest) and Szárliget (50 km west) from 120 km/h to 100 km/h. 

MÁV says it had planned to rebuild the affected section in early 2024, but the government ordered an immediate start to work, which commenced on September 18. 

The state railway company says it intends to complete the project before the end of this year. A single track will remain open until October 26, when both tracks will be shut.