Unfortunately for BMW the early K1200S models suffered snatchy fueling and a notchy gearbox. Mid-year model revisions were implemented in hopes of eliminating a closed throttle surging issue, but the fixes seemed hit-and-miss. BMW plainly admits a misstep or two when press materials state that the “2009 K1200S and K1200GT were reworked to address the shortcomings of earlier models.”The first order of business in the ‘09 K bike was raising displacement from 1157cc to 1293cc via a 1mm overbore and 5.3mm increase in stroke. Additional changes include lighter pistons with thinner rings.
A “step” in the intake port is aimed at improving combustion with the result of increased torque, power, fuel economy and cleaner emissions. Other enhancements are new fuel mapping to improve “partial-load situations,” a new dual-throttle cable (as opposed to just one from before); an idle control valve now made from metal rather than plastic, and the exhaust valve timing was revised. The airbox was redesigned as were ram-air intake ducts. The objective behind the majority of those changes was cleaning up the sometimes-unpredictable throttle response the K1200S exhibited.
