the top three fins on the head have been removed, they weigh a kilogramme each, the rubber mountings are daf lorry parts to damp out vibration and lower the engine in the frame to give a better c.o.g., the tiny brass tube drilled into the float bowl on the carb is for a breather to stop fuel cavitation, the original drain from the float bowl will exit into the frame catch tank but if fuel reaches it then the carb will lose atmospheric pressure and not breathe correctly causing poor carburation hence the modified breathers.