Well I'm convinced this is a KM24.
it has the small 4 screw tappet cover, not the large M20 version & looks like the pushrod tower with 2 side bolts.
The head is surely ohv although the angle makes it tricky to see
I actually came to the site when looking for M20 parts for a German friend (I also happen to be building an M20/24 race special)
Very nice to find the pic!
As the angle is so tight, it could possibly be one of the experimental WB30's that was cast a little like the '49 Gold star but in cast iron
It's not a WB30..There are a number of elements that rule that out..The four screw tappet cover indicates a 1939 spec. M24 and it has the right tank, forks and gearbox for that model...Ian
