How about enforcing laws against cyclists that constantly break traffic laws?
Cyclists get fined, and they can even loose their driving license (for cars).
These checks are not too-frequent (neither are those for car drivers), but they exist.
And read this, as it suggests sticking to the rules may be more dangerous for cyclists.
http://www.theguardian.com/uk/2010/may/21/women-cyclists-mos...