Yamaha S80 Service Manual "S80A4_E" (PDF 5.2MB).
Yamaha S80 Service Manual "S80CB5_E" (PDF 2.5 MB).
Yamaha S80 Service Manual "S80e" (PDF 291K).
Yamaha S80 Service Manual "S80MAIN_E" (PDF 1.6MB).
Yamaha S80 Upper Keyboard Assembly Diagram (PDF 179K).
Yamaha S80 Combined Upper and Lower Keyboard Assembly Diagram (PDF 49K).