Engine rattle/tapping on startup

[simmo]

If oil level is even just slightly low, it takes longer to lubricate the upper engine parts.

If the oil level is ok, do as I have suggested in other discussions, warm the bike up for 20 to 30 seconds at above 2,000 revs. ( per the handbook ).

As per Busgo warm engine at 2k otherwise your motor is not getting full oil pressure and thats not good, you don't have to warm it up for long, by the time you gear up is plenty....