I’m still trying to get my head around the adj valve timing.
It’s really not that complicated Jim
With fixed timing like our bikes the cam drive gears position remains constant in relation to the lobes. The new VVT can change the position of the drive gear in relation to the lobes thus retarding or advancing the cam timing. It does this using oil pressure, forcing oil into a dual sided chamber. To retard oil pressure is directed into one side, while the other side is not pressurized. To advance the pressurized side is switched.
Now all this does require a cam position sensor so the control system detects the relative position of advance or retard. That protrusion on the front of the cam cover is where that sensor is.
I read somewhere that the cam can be advanced 20 degrees or retarded 20 degrees. That seems like a lot to me. Maybe they really meant plus 10 or minus 10 but that is still a lot.
The net effect is that a cam with more duration and lift can be used and still pass emissions because of the adjustability.