The bike, being out in public, has no reasonable expectation of privacy.

This is a real source of pain for certain celebrity bikes, which can't go anywhere without a gaggle of photographers or 'bicilipaparazzi' following them around and (arguably) making their lives impossible. A hot-tempered young bike, once a member of the 'Brat Bike Pack,' achieved some notoriety some years back by smashing a photographer's camera, but that only got it more attention.