In ATV motocross,
great power output doesn’t
mean much without superior handling.
YFZ450R delivers! Nearly three inches
wider overall than the YFZ450, the
stance of this new 450R is motocross-ready.
The weldless frame is designed of
lightweight aluminum, with a tension-steel
bottom frame that lets the engine
sit lower for excellent mass centralization.
Suspension components have more
travel carefully chosen for best
performance, and the front shock
bodies feature Kashima coating for
even smoother operation.
Fatigue can sometimes
be a racer’s worst competition.
That’s why the YFZ450R’s
designers made this ATV so comfortable.
It’s much roomier, with plenty
of room to hang off in the corners,
and the seat is padded just right
to be more comfortable regardless
of riding position. Handlebars are
4-position adjustable, too, so every
rider can choose the best position,
and the throttle has been designed
for all day comfort. What’s
more, the engine balancer has been
revised to even further reduce vibration.
This 449cc engine
uses the cylinder head and cylinder
from the championship-winning YZ450
for awesome power output. That means
titanium five-valve cylinder head
technology, with a camshaft designed
just for this machine to deliver
abundant low to midrange torque
for performance where you can really
use it to take the lead –
while still maintaining a super
strong top end to let you pull away
from the pack.
The YFZ450R adopts
fuel injection for precise fuel
delivery. With big 42mm Mikuni®
throttle body and 12-hole injector,
this system provides exceptional
atomization of the fuel for maximum
power. The system also includes
ISC (Idle Speed Control) for easy,
reliable start-up and warming.
This ATV is designed
to make race prep easy. Body panels
come off easily for service; there’s
no need to remove the battery or
other components to get the fenders
off. The aluminum frame is bolted
together, rather than welded, for
maximum durability. And the oil
tank is integrated with the crankcase
so it’s easier to service
the engine
Yamaha
YFZ450R ATV Engine
The fuel-injected
449cc engine uses the cylinder head
and cylinder from the YZ450 for
superb power characteristics. Power
delivery is smooth and strong off
the line with lots of low and mid
range where you need it. As rpm
climbs you’ll find the same
top end punch that has made the
YFZ450 such a fierce competitor
and class leader.
The new crankcase
holds the newly designed crankshaft
that’s ready to handle the
increased torque output, as well
as the counterbalancer that has
an increased ratio for superior
vibration control. The crankcase
also houses the oil tank, which
helps to centralize mass for unmatched
handling and makes maintenance easier.
Camshafts are
all new for this model, and are
designed to maximize the torque
available in the low and mid ranges.
Fuel injection
uses a 12-hole injector that provides
exceptional atomization of the fuel
for maximum combustion efficiency
and power delivery. The system also
uses a big, 42mm Mikuni® throttle
body and includes ISC (Idle Speed
Control) for easy, reliable start-up
and warming.
Yamaha
YFZ450R ATV Chassis/Suspension
The chassis is
very spacious, allowing room for
an aggressive racer to move around
during the moto, and the ATV’s
body panels that the rider contacts
during operation are of a special,
softer plastic material for greater
comfort. And the seat is narrow
in the front, yet wide and padded
in the rear to provide a more comfortable
ride, even when hanging off on the
side of the seat in a turn.
Wheels are set
motocross-spec wide, near the maximum
allowable 50 inches, for great cornering
ability. The newly designed Dunlop®
tires are grippy with a great pattern
for cornering, and at 20 inches
in the rear and 21 inches in the
front, provide much better ground
clearance than the competition.
That makes the YFZ450R fun to ride
off-road, too.
ProTaper®
handlebars are mounted on 4-way
clamps for exceptional adjustability.
There are two sets of holes in the
handlebar crown, and eccentric clamps
so the rider can choose the standard
setting, 10mm or 20mm forward, or
10mm back.
Foot pegs are huge
65mm, something riders will appreciate
every time they want to get up on
the pegs, with good kick-up on the
ends for solid footing.
The all-new frame
is aluminum for lightweight, except
for the frame member under the engine.
Here tensioned steel is used to
allow the designers to position
the engine lower overall for excellent
mass centralization for unmatched
handling. The frame is bolted together,
rather than welded, for maxium durability.
The front frame
is noticeably narrow at the A-arm
mounting points. This dramatically
reduces changes in camber as the
long A-arms travel through their
full range of motion. The front
44mm KYB shocks have Kashima coating
for smooth operation with superb
bump absorption and excellent anti-bottoming
characteristics. The 9.8 inches
of wheel travel means this racer
is up to even the most challenging
tracks.
The rear swingarm
is crafted of strong, gravity-fed
aluminum, and it’s matched
to a fully adjustable 46mm KYB piggyback
shock absorber for excellent handling.
Rear wheel travel is 11.0 inches
for comfort even on tough terrain.
For excellent
stopping ability, YFZ450R features
dual front hydraulic disc brakes
and a trick looking, lightweight
wave-type rear rotor.
Additional
Features
Low effort throttle
level which is very comfortable
to use. That means less fatigue
during all-day riding.
The instrumentation
is all business. The discrete panel
on the fender in front of the rider
gives vital indicators about low
fuel, coolant temperature, check
engine, and neutral gear via a straightforward
LED display.