Hi,
Sorry for the lateness of this extra info.
My multimeter was in error. The 9v PP3 battery in the multimeter needed replacing.
The multimeter WAS over reading.
After replacing with a new PP3 battery.
The bike battery read 12.9v.
I used GT85 and saturated the starter switch and cleaned up the switch and checked some of the connectors under the tank all look ok, sprayed them with ACF-50.
After a good charge on the optimate all seams fine touch wood.
In my opinion running the bike on my 8 mile each way commute with dipped beam and heated grips every day over a week.
Drained the battery enough to cause the symptoms.
Currently I have not needed to used the heated grips but still use the dipped beam and the battery seams to be ok.
with no difficulty starting.
We shall see over the summer if I have any re-occurrance.
Cheers for all your help.