Who needs a multi meter? 10 days minus 100% of charge equals an average of 10% loss or 1.4 volts per day, duly noting that the initial loss shall be greater than the latter loss.
Now I am worried. The grammarian in me asks: Did Bazz mean to put a comma after 'simple' and/or after 'Nigel'? One infers simplicity, the infers I'm a simpleton. On second thoughts, don't reply!
A completely flat battery will read about 12v Nigel, a new fully charged battery at rest about 12.9v.
Serious question then, how come a couple of mine read 14.4 on the Oximiser? Is that only a voltage at charge or also at rest? Agree about the starting voltage. I had the RR4 off charge for a short time and it wouldn't start on just over 12V.
That is what the oxidiser charges at . your bike when running will be about 13.5v My optimate chargers them to 13.8v
When you put the multi meter over the solar charger terminals it reads 17.4v but the battery will only take what it wants