Motor cars only

TR117

Where: At the beginning of any road or part of the road.
Purpose: Indicate that a road or part of a road may be used by motorcars only.
Action: You may only drive a motorcar on this road or this part of the road. Where this sign is displayed, you must use that part of the road indicated by this sign. When driving one of the following vehicles, you may use such a road only when the sign depicting your type of vehicle is displayed.

Manual on Road Traffic Signs, page 8.