The K1300S benefits from 136cc more power, with BMW's other superbike cranking out 175 horsepower.
The distinctive front end of the K1300R defines the naked version of BMW's revamped K series.
The improved engine capability of the K motor figures to enhance the already solid GT touring platform. Tuned for power output on the lower end, the K1300GT taps out at 160 hp at 9000 rpm and 99 lb-ft of torque at 8000 rpm. Again, engine changes carry over with the other K models. ABS comes standard, with ESA II and ASC optional. Also changed is a new adjustable windscreen.
source : http://www.motorcycle-usa.com/354/1260/Motorcycle-Article/2009-BMW-K-Series-Goes-to-1300.aspx