The most reasonably priced component used on the Jf650-a2 Jetskix2 1987 United Kingdom Fr Al It Crankcase is the Pin,dowel,10x8.2x14.
The Crankcase is made up of components including this Set-crankcase which is the most expensive.
Some items from this specific schematic: Valve-assy-reed, Cover,control Valve, Seal, Ring-snap.