[DonRotolo]

Moving some weight towards the driven wheels will help. The force needed to turn the bot is increased when the weight is close to the omni wheels. Try this to see what I mean: Swing a sledgehammer in a circle, first with the head away from you and then with the head in your hands. Do you need more force to swing it when the head is in your hands, or less? That force comes from your wheels, and a single CIM is reaching the upper limits of the torque it can provide.