MercerAUST

Try the low settings, half a turn at a time richer (clockwise). It should respond. If it does not, set both needles to the recommended default (make sure you are using the American instructions (available at Horizon Hobby website) and not the original Japanese translation (where the number is incorrect).

If this does not work and you have checked the spark plug gap, fueling is good (try blowing gently down the breather vent line to increase tank pressure and open the throttle to see if this works) then it might be the ignition/timing. This seems unlikely if it starts OK.