I found a guy who has built a quality passenger backrest for the K1600, which he is selling on another forum. He is in the process of building 12 units, and many of them are already sold. I'm buying one for my K16GT, as my wife is needing some support, and I do not want the BMW top case. The backrest would also be good for some who already has a top case, and just wants something lighter and with less bulk. Here's a link to the thread - there are pics and a video scattered throughout. If you're interested, just post accordingly if you're a member. If not, then send me a PM with your email address, and I'll put you in touch with Dan (DUSAK).