How do I ride the go-karts on bully for xbox 360?

When I went to ride the go-karts it did'nt have that blue circle so I don't know how to get in , does anybody else know?|||it depends what chapter your in, you need to ride the ones in the carnival first, then one opens up in old bull vale near the bike shop at 12pm, then the last one opens up after you get to chapter 5. need any help gamertag is gt rep i have all the achievements so if u need im willing to help