Cyclists only

R111

Where: At the beginning of any road or part of a road.
Purpose: To indicate that the road or part of the road may be used by cyclists only.
Action: Do not use the road or part of the road indicated by this sign. Cyclists may use only the part of the road indicated by this sign. Version 1.00 6 Jun 2012 Copyright © 2012 by SA Department of Transport

Manual on Road Traffic Signs, page 7.