To discover exactly which parts you require use the on-line schematic exploded diagram - it will even give you some idea of where and how to fit those new parts.
The Yamaha YBR125ED 2005 3D91 TURKEY 1D3D9-300E1 parts lists consist of forty schematics.
YBR125ED 2005 3D91 TURKEY 1D3D9-300E1 section with forty Other schematic pages.
