The most expensive part in this assembly is the Crankshaft-comp.
The most reasonably priced component used on the Ke125-a4 Ke125 1977 Usa Canada Crankshaft/piston/rotary Valve ( is the Circlip-piston Pin.
This schematic depicts all components used in the Ke125-a4 Ke125 1977 Usa Canada Crankshaft/piston/rotary Valve ( partslist.