THE KX THAT IS, THE KX THAT WAS
In a class defined by frequent change, the Kawasaki 450
motor has a very long history. Most of the other brands had
to undergo major redesigns to accommodate fuel injection.
Kawasaki, on the other hand, didn’t reinvent everything
when the carburetor was tossed into the scrap heap in
2009. Instead, the bike maintained a steady program of
change before and after. You can spot the changes in a
Yamaha or KTM motor from space, but that year, Kawasaki
just gave the KX450 EFI, a new head, and a bunch of new
part numbers. The next year, it got a new piston and cams,
and so forth. The basic DNA of the bike never changed; it
remained a DOHC, four-valve, wet-sump four-stroke true to
the original concept that appeared in 2006.
In 2012, the bike got a couple of significant electronic
features. One was Launch Control, which is still exclusive
to Kawasaki. Launch Control is a system that alters the
powerband for a more controllable start. You just push a
button to activate the system, and the ignition is retarded
slightly. When you shift into third gear, the mapping returns
to normal. Another electronic feature is the multi-map ECU.
The KX’s brain can store three different ignition/fuel mapping curves, and they can be switched at the track within
seconds by using color-coded electronic plugs. The stock
plug is green, the richer one is black, and the leaner one is
white. Kawasaki says the rich map is for hard-packed soil
and the leaner curve is for sand.
That program of gradual change continued last year
when the KX got a 48mm KYB pneumatic spring fork. This
eliminated traditional fork springs entirely and reduced the
bike’s weight by 1.7 pounds. It also provided a new degree
of adjustability, and the performance was excellent. The
trade-off was that the forks required riders to check their
fork pressure just as they would tire pressure.
Kawasaki sent the 2014 KX450F
back into battle with a handshake and best wishes. It was
good enough to give the development guys some time at home.