Was ist das ? Yeah, that’s what comes to mind when seeing an Apfelbeck cylinder head. A very unusual design seen in the sixties in motor sport and particularly with BMW and their early Formul…
If I remember correctly one of the Italians also tried a similar layout of the valves, maybe Alfa or Maserati?
The first I heard of this Apfelbeck head/engine was in a book about "best racing engines" or something like that. It may have been "legendary car engines" as that looks familiar.
Exactly, the interesting part is the diametral valve positioning, which means that there's always a intake- and an exhaustvalve sitting opposite to each other and beside each other in an hemispherical combustion chamber. Check how the valve train is designed......
But it did not sucseed - great in theory but too many other disadvantages.
Yes, I have the very same book but never saw that engine in reality until last week at the BMW museum in Munich.
Not sure about the KTM.... radial valves is one thing but the diametral orientation the other.....