hundreds of hours
before a rebuild. The
location of the airbox
plays a small role in this. The element
seems to stay much cleaner than
those of other bikes. The clutch is
strong, the gearbox is solid, and the
engine, as a whole, is stone-reliable.
The engineers might have hoped for
this, but no one expects a radical
new design to be so trouble-free.
Another strength that remains to
this day is the suspension. With all
the new fork designs that use one
spring or none, it seems like the KYB
SSS fork should be showing its age.
Not so. In fact, the new forks coming
from all directions simply underscore
the qualities the Yamaha suspension
has had all along. Heavy riders, light
riders, fast guys and slow guys universally praise the YZ’s suspension,
especially in front. It remains the
standard that all others must match.
And then there’s the power. The
Yamaha isn’t the fastest or the slowest 450, but it might be just about
right. No one gets off the track complaining that the YZ can’t keep up.
The power starts low and progresses
nicely to a screaming over-rev, but it
doesn’t wear you out or scare you. It
has a very smooth delivery, like most
EFI bikes, but it also has just enough
hit to be fun.
DID SOMETHING GO
The reason that the YZ didn’t take
over the world is because it didn’t
quite accomplish its stated goals. The
rearward-tilted motor was supposed
to make it feel nimble, but the bike
feels large, long and a little heavy.
That isn’t to say that the concept isn’t
valid. The move to fuel injection
That didn’t mean that Yamaha was
wrong in the first place—just that
valve material had progressed to the
point where there was no real weight
advantage in having three smaller
intake valves as opposed to two big
Yamaha also joined the rest of the
industry by going to a twin-spar
frame design (Yamaha calls it
“Bilateral Beam,” just to be contrary).
This was done to make a straight
shot from the airbox to the head possible with no frame backbone in the
way. The bike also has very high-quality components, like the oversize
bars, wide pegs, Excel rims and
Braking rotors. It remains a bike that
is both engineered and built very well.
So why didn’t the 2010 Yamaha
YZ450F take over the world? With so
much going for it, it seems like it
should be the only bike on the starting line. What happened? As it turned
out, the new YZ450 was a great
motorcycle, just not great in the ways
that Yamaha engineers envisioned.
The 2010 YZ, just like the 2013 version we have here, excels in three big
categories. First, it is the most reliable
bike in the 450 class. The bike was
The YZ450 is unchanged for
2013—aside from graphics
and the $8490 price tag.
The reverse cylinder is designed to
centralize the mass of the motor and
make the bike feel light. As with all dirt
bikes, the move to fuel injection added
reasonably well, but you have to ride
it aggressively. There’s no lazy
approach to getting around the track.
In turns, you have to roll the gas on
early to kick the back end out and
move your weight forward to make
the front wheel bite. The tilt of the
motor might well make the bike feel
lighter, but there’s no denying that it
also takes weight off the front wheel.
It’s no big deal; Yamaha’s handled
that way before the redesign.
There are a number of other odd
things that take some getting used to.
The airbox makes a loud sucking
sound, and it’s pointed right at your
face. You get over it. The motor is
also very lurchy just above idle. Don’t
misunderstand; the power delivery
itself is very smooth and linear, but
the transition from “off” to “on” is like
a toggle switch when there’s no load
on the motor. You don’t notice it on
the track as much as in the pits or on
a trail ride. The issue was much more
pronounced in the first year of production.
Even now, in its fourth year, the YZ
remains controversial—even more so
after James Stewart left the JGR
Yamaha team. The truth is that what
James likes or doesn’t like in a
motorcycle has nothing to do with the
rest of us. He’s Bubba; you’re not.
But if you’re looking for a reason not
to like the YZ, you can probably find
it. On the other hand, if you don’t
have some preconceived notion
planted by someone else, chances
are that you’ll like everything about
the bike. As for us, the YZ still ranks
high on our list. It’s bold, it’s innovative and it’s great at certain things.
Best of all, it’s not boring. ;
YAMAHA YZ450F YAMAHA YZ450F MX TEST