As others have said, I think this is your problem. I use a cheapo bike stand (£30 from Halfords) to wash mine right side up.
There will be holes into the frame for cables and hoses around the motor and water would be getting in through them.
The Sellaronda in the Dolomites, one of the best days out on the bike I've had. I did the anticlockwise with the climbing, but it looks pretty much the same as the clockwise.