Cyclists racing down narrow tarmac path

Since the removal of the double staggered barriers and the replacement with a single barrier there has been a dramatic increase in the number and speed of cyclists illegally using this narrow path and zipping past the end of 2 blind driveways. Can we suggest a clearly marked hand post is attached to the edge of the barrier so that it is just above handle bar height and will therefore encourage cyclists to dismount as they used to have to do with the old barriers. This solution should help address the problem before an accident happens, especially it is used by many young children walking to school, and without reducing the accessibility for wheel chairs and buggies.