An agricultural system includes a baler with a plunger and a sensor for sensing a plunger-related value； a vehicle including a power source operable to convey power to the plunger； and a CVT arranged to drive the plunger. In order to balance a fluctuating load of the plunger over the working cycle, an electronic control unit (ECU) is coupled to the sensor and to the CVT and is configured to receive the signal from the sensor and to cause the CVT to modify a gear ratio of the CVT based on the signal from the sensor and on a mathematical model defining a CVT gear ratio variation profile derived from an expected load applied by crop on the plunger over its operating cycle.
