......Anybody use the Sherpak???....
I have two of them, one large, one just the right size for the luggage
carrier on my Westy.  I use the smaller one frequently, tie it down with
a set of bungee cords to the tie down points in the luggage carrier.  I
have had mixed results in the rain.  If I am VERY careful with it, I
only get a minor amount of moisture inside.  If I'm not careful, it
get's flooded. I only store items that can get wet (folding table,
folding chairs, etc.) up there.