(1) It shall not be lawful for any person to drive a mechanically propelled vehicle in a public place in which no special speed limit applicable to such vehicle is in force at a speed exceeding the ordinary speed limit (if any) applicable to such vehicle.
(2) It shall not be lawful for any person to drive a vehicle in a public place in which a special speed limit applicable to such vehicle is for the time being in operation at a speed exceeding such speed limit.
(3) Every person who drives a vehicle in contravention of this section shall be guilty of an offence under this section and shall, on summary conviction thereof, be liable in the case of a first offence, to a fine not exceeding ten pounds or, in the case of a second offence, to a fine not exceeding twenty pounds or, in the case of a third or any subsequent offence, to a fine not exceeding fifty pounds.