I was wrong about the 690 design, the head is almost the same as the current 530. Further study reveals that the outward apperance of the heads are the same with the addition of a MAP or temp sensor for the EFI just left and below the spark plug, the cases are different as is the trans and clutch aspects one could assume. Possible good news for those wanting the factory 570 kit or other BB kit which would need only drilling and tapping for the MAP sensor.
This may be KTM
's way of addressing oil transfer issues and the percieved lack of long term durability due to low oil volume on extended rides. Can't wait to get more data. See pics below to compare heads.
New 500exc: note MAP sensor location.
current 530 head: note MAP sensor location as a flat area left and below plug.