acteristics of the Yamaha, and there are others who don’t
care for the overactive feel of the Honda. You won’t find
anyone, however, who complains about the KX’s overall
handling. It’s been like that for years now and is one of the
reasons for the bike’s success.
The same can’t be said about the Showa TAC air fork.
This is the KX450F’s most divisive feature. On one hand,
most riders acknowledge that the fork is so adjustable that
it has the potential to be the best front suspension on the
market. On the other, it rarely works well in the real world.
The problems are usually owner-related. The pressure in
one of the three chambers might be out of whack, and the
rider tries to compensate in the wrong place. That’s why
the aforementioned phone app is so important. It gives you
the proper place to start and tells you clearly what each
change will do.
Stock, the settings are supposed to be 160 psi in
the main chamber, 14. 6 outer and 174 balance. If you
want to make life easier for yourself, stick with that and
compensate with the damping clickers. If you’re lighter or
heavier than the typical rider, work with the main chamber
and then use the balance chamber for ride height (higher
pressure means lower height). For what it’s worth, our
170-to-190-pound riders settled on 155 main, 13 outer
and 180 balance as a good all-around setting that was
cushier than stock.
The rear end of the KX isn’t nearly as complicated. If you
set the sag around 100mm, you can then use high-speed
compression damping to make the ride height feel right
for any given track. Low-speed compression is straightforward and only needs to be increased for really rough
tracks. The Kawasaki rear shock has an impressive ability
to please without much fuss.
As of 2018, the KX has the mildest power output of any
450 MX bike. Kawasaki seems to have bowed out of the
race as peak horsepower has climbed into preposterous
levels. On the FMF dyno, the 2017 version produced
almost 3 horsepower less than the KTM, Husky, Honda
and Yamaha at peak (around 9500), and then fell off dramatically. But down in the basement, around 6000 rpm,
the Kawasaki had a 2-horsepower advantage. You learn to
ride the KX accordingly. The bike is at its best when you
shift early and torque your way around the track. Having
an edge on top might sound appealing, but you need to
be honest with yourself—are you one of the elite pro riders who really needs it? Novices are better off riding at
low Rs, although even they might suffer a little when the
Kawasaki’s low ceiling forces an extra shift before you run
out of straightaway.
Kawasaki has arrived at a neutral handling
package that has no natural enemies.