K1200s

[slparry]

so is there any good reason not to fit the rear wheel from a K1200S :) ?

[DavidTaylor]

I'm assuming you mean the wider rear wheel since the K12S had an option for a 5.5 or 6 inch wheel (180/55 vs. a 190/50 tire). Other than the fatter rear tire may slow your turn in into corners and the style/spoke pattern of the wide rear wheel is different from the standard rear/front so it may look funny, I can't think of any. You should probably double check the swingarm clearance to make sure it fits, too. :)