The oil
Drain bolt is probably open to more abuse than any other fastener on the machine!
Clumsy ill fitting wrenches, adjustable or even Mole Grips have frequently managed to round off the hexagon head!
Due to the importance of this part if you are in any doubt at all with the old
Drain bolt it is really worth renewing along with this
Packing Washer. The bolt vibrating undone depositing oil with potentially disastrous consequences, or worse being stuck fast and having to use a chisel to remove it!
A related part you may wish to consider:
90013230000
Buy a new one - because your motorcycle is worth it! Please make sure that the part numbers you order are compatible with your model.