This on BMW web site ????
Can I load other maps onto the Navigator onto the Navigator III in addition to the pre-installed maps?
Yes, this is possible since the internal memory of the Navigator III is not completely full. Some 800 MB of memory space is additionally available. However, the pre-installed data would be completely overwritten. You can reload the entire set of fine map data at any time using MapSource, but this process can take some time.
Can I still load the internal memory of the BMW Motorrad Navigator III myself in spite of the pre-installed map data?
Yes, that is possible but not necessary since map data for the whole of Europe is already installed. The Navigator III is supplied with the entire MapSource City Navigator software which can be used when loading routes and waypoints onto the device. Map data can also be loaded but the pre-installed maps would be entirely overwritten. You can use MapSource to reload the entire set of fine map data into the Navigator III memory again, but this process can take a very long time.