In message , at 08:28:24 on Tue,
7 Sep 2004, John Rowland
remarked:
http://www.highwaycode.gov.uk/sign071.shtml

means 'Route to be used by pedal cycles only'.

Except I don't think that would apply to a full-blown road.
You need a "no entry" to stop the motorised traffic.

The safest way to achieve this would be to put in a traffic island 1 metre
from the kerb, and have No Entry signs on the large entrance, and Cycle Only
signs on the small entrance.

Yes, and this is done from time to time. Not all roads are wide enough
for this, though; including the one in Peterborough that I've mentioned.
It's only wide enough for one car and the contra-flow bike lane.
--
Roland Perry