This chain size is becoming one of the most popular.  With modern steels and manufacturing techniques, it is now possible for even high-performance superbikes to use a relatively light weight, low friction chain.  There are many variations including different sealing options to keep lubricant in the right place, lightened, drilled side plates, narrow plates and colours, so take a good look around to find one that is perfect for you and your bike.  Pitch size is 1.588cm, link width 6.35mm and roller diameter 10.16mm.