One good trick that urban bike messengers use (besides riding very simple 1-speed bikes with few components to pilfer) is to glue a nice fitting ball bearing into any hex head bolt so that the bearing would have to be painstakingly dug out before removing the part. Some pedals attach with a hex key only. So if you were worried about someone just stealing the pedals (as the OP headline suggests) then you just get those style pedals, install, then glue in the ball bearing.


Source: https://www.bikehacks.com/bikehacks/...art-theft.html