The following section is substituted for section 47 of the Principal Act:
(1) A person shall not drive a mechanically propelled vehicle at a speed exceeding the speed limit -
(a) that applies in respect of that vehicle, or
(b) that applies to the road on which the vehicle is being driven where that speed limit is lower than that applying to that vehicle.
(2) A person who contravenes subsection (1) is guilty of an offence.
(3) In this section "speed limit" means a limit which is -
(a) an ordinary speed limit,
(b) the built-up area speed limit,
(c) the regional and local roads speed limit,
(d) the national roads speed limit,
(e) the motorway speed limit,
(f) a special speed limit, or
(g) a road works speed limit.".