I don't have TG, but you might want to check out Hog Trough holders. I love mine. Put a removable rear one on for the wife...
I actually have 3 of them, found the dual front cup holders on EBay for $60.
Look at "Chubby Cup". I have one on my '12 and it clamps to the handle bar. The way it is made there are many different mounting options on the bars. They also have one that can be mounted to the controls (this would not work for me on the left side because of the reverse switches). Plus they don't move around.
I prefer to use my left side saddlebag as my cup/beverage holder. Hence, no splashing onto tank or bike, it's out of the sun and keeps cool longer, less clutter on handlebars.