I don't know how fuel quality is in OZ, but in the USA modern commonly available fuels have complicated the art of plug reading to the point where IMO only gross/obvious indications of way rich or way lean conditions are meaningful by general observation.
By the time overly rich or lean indication clearly shows on the plugs you would already know from other seat of the pants indicators.
FWIW plug reads are useful, but you've got to take them with a skeptical eye, even if you're doing specific RPM/load plug chops.
Hey Staffo, those are great looking pipes, & appear to be worth every cent!
