Information and communication are key to the intelligent city of tomorrow. Many technologies have been designed to connect smart devices to the Internet. In particular, public transport systems have been used to collect data from mobile devices. Public bike sharing systems have been introduced as part of the urban transportation system and could be used as the support of a mobile sensor network. In this paper, we introduce the "Internet of Bikes" IoB-DTN protocol which applies De-lay/Disruption Tolerant Network (DTN) paradigm to the Internet of Things (IoT) applications running on urban bike sharing system based sensor network. We evaluate the performance of three variants of IoB-DTN with four buffer management policies. Our results show that limiting the number of packet copies sprayed in the network and prioritizing generated packets against relayed ones, improves on low loss rate and delivery delay in urban bicycle scenario.