Already receiving a substantial overhaul in 2009 and several engine updates for 2010, Kawasaki has added a number of minor updates to the KX450F for 2011.
Kawasaki has tweaked the shape of the bridged-box bottom piston, introduced in 2010, to work with a new higher-volume muffler that is quieter than last year’s unit in order to meet AMA Pro Racing’s 94 dbA limit.
According to Kawasaki, the electronic control unit has been updated to provide a hotter, longer-duration spark to improve response at low revs. An optional ECU setting tool offers a selection of different data maps and fine tuning of custom maps for fuel injection and ignition timing. A data logger records up to six hours of information.
Suspension has been tweaked, though the KX450F does not get the new Separate Function Fork system introduced on the 2011 KX250F. If it works as well as Kawasaki hopes, the Separate Function Fork may be included on the 2012 KX450F.