It is necessary to precisely cope with an increased lateral force due to speedup of a body tilting car as the whole of track maintenance.
When track rehabilitation progressed in Northern Line is completed, it may be almost possible to cope with the increased lateral force though countermeasure is needed to a certain extent such as maintenance particularly for a small radius curve.
It is necessary to decide the range of speedup on curves by completely considering the synthetic maintenance capacity of a track. By applying the present synthetic maintenance capacity to a reinforced track of Northern Line, it is considered that the study on a speed of a very high level can be expected.
