BindingNavigator allows you to navigate through data records, while RadChart's purpose is to display all the records it has received. So, unless you need to show a single bar/point in the chart at a time, I am not sure this approach is applicable. If you need to show only part of the data in the chart, you will need to split your data into several parts and send one of them to the chart at a time.
the Telerik team
Q2’11 SP1 of RadControls for WinForms is available for download (see what's new); also available is the Q3'11 Roadmap for Telerik Windows Forms controls.