NSR150SP Telltale hold leakage

IIf you found some oil leakage form telltale hole, the mechanical seal and pump shift may damaged or rusted. 

Refer tin above two picture, the mechanical seal has broken and include many rust, the pump shore rusted also. That is, the engine oil will leakage form telltal hole. 

How to fix it?

Change mechinal seal, oil seal, bearing, and pump shift.

The oil will not leakage again