Working and commenting on my experience with XR series RG500's - The XR designates a complete made and sold by Suzuki works/factory spec racing bike as opposed to the standard racing bike anybody involved with racing could go and buy for want of better descriptions, the XR series RG's looked the same but the motors were quite different inside along with other different spec/material parts fitted. Not wanting to get into anything heated I think with the XR69 is possibly defined as a totally different machine by the frame/suspension/wheels etc it had which were made for racing purposes only and not in anyway road based like previous incarnations - it was an out and out racing bike with a GS1000 derived motor. Evolution/offshoots from the same species is one thing - two totally different animals is another.