Parts such as the Crankcase: Breather, Cover, Crankcase 2, P1n, Dowel, Holder are included in the Yq100 2001 5me4 Europe 215me-300g1 Crankcase parts fiche.
On this parts fiche the Bolt,socket is the most specified component.
Of all the components that make up this Crankcase the Circlip(1ey) has the lowest price.
