There is a default transition duration (the time it takes for the chart to be shown with an animation), but this cannot be configured with a public API, so you can use the following forum thread for an unofficial way to configure that:
Regarding the delay - you can read our help articles about performance optimizations and use some of its suggestions to speed up the loading:
Do you need help with upgrading your ASP.NET AJAX, WPF or WinForms projects? Check the Telerik API Analyzer
and share your thoughts.