The axels are not strong enough, the brakes too weak, and the trains have to make repeated trips to the workshops, leaving timetables in chaos - and now kicking off court cases.
The paper said Deutsche Bahn had filed two suits in both Munich and Berlin, claiming a total of €160 million in compensation from Bombardier.
The complaint concerns more than 200 regional trains in operation in southern Germany which have experienced repeated problems with tilting technology and axles.
The Munich case concerns trains which have had repeated braking problems, forcing the federal railway office to reduce the speed limit in the region at times. Initially Deutsche Bahn is not claiming compensation in this case, but wants to force the release of information which it can later use for such a claim which the SüddeutscheZeitung said was planned.
Deutsche Bahn confirmed the existence of the two complaints to the paper, but declined to say what they were about. Bombardier also said it would not comment.
Bombardier, alongside Siemens, is the most important supplier of trains to Deutsche Bahn and primarily supplies local and regional trains.