Hi Pleiades

Thanks for the welcome.

Checked everything again before I left the office yesterday and there was enough water in the expansion tank. Started the bike and left it idling till the fan came on. No water pushed out and the fan ran fine.

Went home last night and gave some stick doing mostly 140 kph on the way home. Checked the water level when I arrived and all was well.

Drove to the office again this morning and all was well again.

So...all I can think off is the expansion tank's cap/plug must have vibrated loose and dumped most of the water when offroad. Some of the roads were badly corrugated so lots of vibes.

Next thing will be to flush the system (was on the list, just not so soon) and make sure there is fresh coolant in there. And keep an eye on that plug/cap of the expansion tank...

Cheers...

Dean