Hi Vrank..Put a wire into the F and D terminals...then join the ends of the wires. Set your meter on the 10 or 20 volt DC range. If you have a negative earth system put the dynamo wires to the positive side of the meter and the negative side of the meter to earth on the dynamo body.
Output can vary but you should get around 2-4 volts at just over idle and 10-12 volts at around 1000 rpm...take quick readings and don't hold the throttle open for too long at the upper end of the output..Ian