Newgates range of Manual Rising Arm Traffic Barriers come complete with locking facilities as standard. This is usually via a 25mm diameter locking bolt at the pivot end of the Barrier.
However, a lockable tip support post is also available, also as a standard.
This client has invented his own locking tip support and has incorporated a bicycle lock, never thought of that!
My only question is, has he left his keys in the lock, and was there a bike attached to it?
For all Barrier enquiries talk to the experts, for all bike lock enquires talk to Halfords or a good bike shop.