hearing no comments or suggestions, i purchased the Kruzer Kaddy KR500,
I use one of these Ram Mount ones, works great and also acts as a holder for sweets when I am not carrying drinks.
Ah ha!! A man after my own heart John. I like Ram Mount stuff, they make good quality at reasonable prices, or at least as reasonable as it gets for Goldwing Farkles and we can buy the stuff over here easily. It all integrates on the Wings so easily and I now have two double ball mounts, one on either side which take all I need. Left side for camera and GPS and right side for phone holder and drinks container.I use this same one and love it!! I can easily move it anywhere I want with the ram mounts and I can clip my garage door opener to it and still have room for a drink. When I don't have a drink, it makes a great holder for my cell phone as I can see the phone with the opening in the cup holder running down the side and I can run the charging cord through the bottom of the cup holder. Very versatile cup holder.
In order to combat the problem of being top heavy I modified my bike bouy to fit the larger drinks and taller water bottles...I lowered the center of gravity by making the swing longer....