My question involves personal property located in the State of: Illinois (Cook and DuPage Counties specifically)

We live in the south suburbs of Chicago, and a few years ago while I was underage my parents gave me a new bike for a present (as my old one didn't work anymore). A few weeks ago, when I was packing up to go to college for the first time they told me they were forcing me to leave my bike behind so that for their own personal use. Legally, what can I (an almost-broke college student) do to get my bike back from them?