So $80 later the new battery arrived was set up and charged and installed.
Instant start even after a four day stand down, so all seems good
I was however interested by the small yellow spark, and humming noise when I reconnected the earth terminal? I disconnected and then reconnected, still a small spark but the second time no humming noise? When I turned the ignition on everything was great except that the rev counter swung up to centre position and stayed there and the digital display didn't do the whole 0-200 thing. I turned of waited a few seconds and tried again and we were back to normal
I know there's a small drain keeping the clock going etc, but I'm interested to see what the drain is. I suppose I'm going to have to plumb the depths of the shed in search of the multi meter.... picture a spacious double garage condensed into a 2.5 x 3 metre shed....
Anyway, now to plan this weekend's ride. South I think!