I received my new Baby a few weeks ago, and am still a few weeks away from getting seriously stuck in to the restoration. I was in the garage this morning working on another bike, and for some reason, decided to pop the side cover off the A10 engine, which wasn't too difficult as it was only held on with one screw. I got a puddle of what appears to be water. I had an oil pan nearby, so it didn't make too much of a mess. God knows how it got there, and if there is more further inside the engine and gearbox.
It doesn't look like it has caused any corrosion yet, but I am going to have to investigate further before it does.