There should be about 2mm of slack in the twistgrip before the cables start to move on the K0. Also, check to make sure the #4 cable did not pop out of the top of the carb (or maybe one of the others?), which will lift that slide and make it idle fast, too. Moving the bars around, or the grip, can make the ends of the cables pop out of their holders at the 4-way junction (or one of the 2 two-way junctions, if yours has that cable version).