The executive in charge of Australia's largest shared bike fleet is surprised by the level of vandalism it has encountered since appearing on streets three months ago, but claimed damage would reduce as bike-sharing became mainstream.

Obike, a start-up from Singapore that raised $US45 million in August after only renting its first bike there in January, has put 1250 two-wheelers on to the streets of Melbourne, and 1000 into Sydney. A Chinese-backed competitor, Reddy Go, has put 1500 bikes into Sydney since July.