Aero Engines at the Deutsches Museum

The hollow propshaft reduced weight & allowed the use of a fire thru cannon.

The spur gear off the propshaft for the shaft driven valve train.

The shaft drive system

The crown gear driving the cam.

A close up of the valves reveals one lobe per exhaust/inlet. The valves are linked by a yoke allowing the single lobe to actuate both valves.