Radius 30cm large disk

Radius 18.5cm small disk

large disk: 2.85kg

small disk: 3.06 kg

2.2x2x3.14=13.8 rad/2.7s=5.16 rad/sec initial angular speed large disk

small disk is 0 initial angular speed

small diskMoi=5x3.06x.185^2=.05238

large diskMoi=5x2.8x.3x2=.126

final angular speed=3.16 rad/sec.
What did I do Wrong?