The first step is to make note when you hear spark knock. At what RPM does it occur,, under what type of load condition does it happen and what % of twist grip does it happen.
The spark advance curve(s) is always changing while ridding the bike.
(1) Make a note of when it happens. (above conditions)
(2) Print a copy of BOTH spark advance curves for each cylinder.
(3) Reference or COMPARE those times you heard knock to the spark curve maps.
(4) Reduce the advance in those cells areas where the knock occurs by 3* at a time.
If you want, upload a copy of your curves so we can see them and state exactly when and where you hear the knock. (That is, what RPM, % of grip and amount of engine load).