Dunno about that, i have a pic on an old hard drive and it pretty much looked like a high port, pent roof, four valve head with finger tappets. Admittedly, the photo was very grainy.
I think the innovation lay in the 111 degree engine block, and the headaches they had to overcome to balance the motor.
The NSR500 two stroke had a 111 degree block angle, and an odd firing pattern V4, they cant have been two shared journal v twins otherwise the crankcase gases could not positively displace the cylinder for filling. It had 3 carburettors.
That can of worms requires a higher level design theory beyond my current understanding.
