You need to be aware that the main limiting factor here is the saturation point of the motor iron, which is determined by the volts per hertz ratio.
The motor is rated 230 V, 60 Hz, for a rated V/Hz of 3.83. you have applied it at 240 V, 50 Hz, for a ratio of 4.8.
This means that the motor was operating well above its rated saturation limit, which would have led to overheating and eventual failure.
The trick to this is to use a stepdown transformer to maintain the rated V/Hz - in your case, the maximum voltage should not have exceeded (50x3.83)=191.5 V.
There is another consideration, which is that the motor cooling fan is also operating slower than rated and hence providing less cooling air, all of which adds to the heating problem.