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By: Jason Giacchino
2009 Yamaha YFZ450R
Yamaha Ups the Ante in the 450 Class
YFZ450R
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Getting Up To Speed
There is a pretty interesting trend going on
in the performance segment of the ATV market
these days in that each of the big seven
(Yamaha, Kawasaki, Suzuki, Honda, Can-Am, KTM &
Polaris) have suddenly realized that quad racers
aren’t going to settle with “almost-race ready”
equipment much longer. Case in point: Yamaha was
already aware of the potential of their YFZ450
in stock trim but wanted to offer prospective
customers an even more MX-inspired model for
2009. Enter the
YFZ450R, an all-new motocross
weapon that will actually share the model line
with the more trail-friendly YFZ450. Sure they
could have just tweaked the existing model to
extract a bit more power out of its mill; but
things are happening fast in the MX market of
late, and Yamaha doesn’t intend to play second
fiddle to the likes of the new KTM SX line or
the Can-Am DS450MX. Yamaha hit the ground
running with this all-new R model; and if
there’s one safe bet to be made, it’s that ATV
racers are finally being taken seriously at the
OEM level.
We’ll begin by examining some of the
differences between the standard YFZ and the new
YFZ-R. Nearly three inches wider overall than
the YFZ450, the stance of the new 450R now comes
motocross-standard at 50 inches. The frame
itself is made of lightweight aluminum, with a
tension-steel bottom section that allows the
engine (and rotating mass) to sit lower for mass
centralization. Suspension components will offer
nearly an inch of additional travel, motocross
specific damping. Up front Yamaha spec’ed 44mm
KYB shocks with Kashima coating for smooth
operation, increased durability and excellent
anti-bottoming characteristics (9.8 inches of
travel). The rear swingarm is crafted of
gravity-fed aluminum and matched to a fully
adjustable 46mm KYB piggyback. Rear wheel
travel is 11 inches.
Additionally the new chassis allows for
relocation/ rearranging of the cockpit. The goal
is to create a much roomier platform, with
plenty of room to hang off in the corners and to
move around on in the air. ProTaper bars come
stock and are 4-position adjustable too, and the
throttle has been designed for all day comfort.
What’s more, to counter the reputation of
aluminum as being rigid and teeth chattering,
the engine’s counter-balancer has been revised
to further reduce vibration.
Yamaha didn’t have to look far to find a
suitable power plant to stuff into their new
chassis as this 449cc mill uses both the head
and cylinder directly from the
championship-winning YZ450F: Titanium five-valve
cylinder head technology, with a
specifically-designed camshaft to deliver
abundant low to midrange torque while still
maintaining a potent top end for those tracks
that require riders to hold onto a gear until
the cows come home.
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Carburetor holdouts will be saddened to hear
that but another machine is waving goodbye to
the concept of needles and jets in favor of EFI.
The
YFZ450R joins a long list of
performance-oriented quads to adopt fuel
injection for precise fuel delivery and
electronically controlled fuel management. With
a 42mm Mikuni throttle body, 32 bit ECU, and
12-hole Denso injector, this system provides
exceptional atomization of the fuel for maximum
efficiency. The system also includes Yamaha’s
Idle Speed Control (ISC) system to make for
reliable start-up, warming, and dreaded
hot-start performance.
Details, details… Remember the days of having
to remove half a dozen fender bolts to reach
your air box? Well, Yamaha wants to help you
forget about that as the new 450R has been
engineered to make preparations and maintenance
specific to racing a snap. Body panels come off
easily for service; there’s no need to remove
the battery or other components to remove the
plastic. Like the Can-Am DS450, the aluminum
frame is bolted together, rather than welded.
Also, the oil tank is integrated with the
crankcase to make engine service less of a
hassle.
Even the foot pegs haven’t been overlooked.
The
YFZ450R will feature 65mm wide stockers with
kick-up on the ends for solid footing.
Interestingly, Yamaha has opted to stick with
20-inch diameter rear tires (bucking the trend
of the typically considered superior 18 inchers
for MX use) in the form of all new Dunlops: 21
inches front/ 20 rear.
Finally, wavy rotors for improved heat
dispersion come stock all around and even the
instrumentation has been relocated to a fender
panel so as not to complicate the bars.
Yamaha claims the wet weight of this machine
at around 405 pounds, placing it pretty close to
the weight of the standard YFZ450 (which was
around 350 pounds/dry).
As with any model this new and anticipated,
Yamaha understandably asks that test riders come
to them. As such we sent a rider up to Gorman,
California to spend some saddle-time on both the
trails and MX track (side note: it didn’t take
much convincing to wave goodbye to the
snow-buried trails and blizzard-like conditions
of New York to test out in sunny California).
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