Configuring Levels of Top-Level Navigation 
You configure the levels of top-level navigation by setting a property in the Ajax Framework Page.
In the Portal Catalog, choose .
This folder contains the Ajax Framework Page.
In the context menu of the Ajax Framework Page and choose .
Select the Ajax Top-Level Navigation iView, and choose Open.
Choose All to display all of the properties of this iView.
In the Properties editor, from the Show Category dropdown list, select the Navigation property category.
In the Number of Display Levels property, select the value 0, 1, or 2, depending on how many navigation levels, if any, you want for top-level navigation. Levels following this number continue in the Detailed Navigation iView.
Caution
Choosing 0 removes top-level navigation and displays the entire navigation structure in the Detailed Navigation iView.
Save your changes.