Hi,
I have a grid and it's datasource is a datatable. The datatable binds the grid in Pageload . there is another grid in the page and second grid's databinding is done according to first grid's clicked row.
Try moving your grids' binding logic to the NeedDataSource event and then try the suggestions from this forum thread:
http://www.telerik.com/community/forums/aspnet-ajax/grid/codebehind-version-of-the-master-detail-selectedvalue-sample.aspx