Here is a possible solution to your dust problems; it has worked very well for me. First, you will need to have both the front and rear windshields from Honda or something very similar. Next, you will need to open the front windshield releases so that you can put two longer braces (11.5 inches) in place. This will create an airflow that will keep out the dust and provide a cooler riding experience. Sorry, this provides no help for anybody in the back. By the way, keep the back windshield closed!
See pictures:
Big Red Pictures :: Windshield, driver picture by dwfleming1 - Photobucket