hmm
My GRiSO makes very little noise: for a big aircooled fecker with pushrods and hy-co camchains and bloody heavy flywheel and a bevel. (compare with Triumphs, Nortons, BSAs, Ducati, Laverda)
But if i wear a different helmet or the wind is from the NW or it is All Fools Day it makes many funny noises. -
My least favourite is an engine speed whine worse at low speed - think it is one or both of the hy-vo camchains
Basically if the noise doesn't get worse, doesn't affect performance and none of the SERVICE or red lights come on - just ignore it