Pap has a cool idea for their clutched machines.
It was probably made to prevent the prop from free spinning during transport, but it can also provide some protection during start. Just like the “Rope Trick,” leave the prop cover on while starting.
If the motor were to accidentally go to power, this would keep it from spinning and give the pilot a chance to kill the motor. A clutched machine, trying to work against a stopped prop, cannot develop full horsepower since it will torque out well below max power RPM depending on the clutch.
If all goes well, once the motor is idling, carefully remove the cover and enjoy responsibly.