| 449cc liquid-cooled, DOHC,
four-valve, four-stroke single |
- Based on the engine from the World Championship
winning KX 450F
- A lightweight forged piston reduces
reciprocating weight
- Triple piston rings and a 21mm diameter
piston pin help increase durability and
reduce necessary maintenance
- The intake ports feature a special coating.
The extremely smooth surfaces improve
intake efficiency at all rpm
- Lightweight titanium valves and aluminum
valve spring retainers reduce reciprocating
weight and boost high-rpm reliability
- Lightweight high-performance titanium
exhaust header contributes to low and
mid-range throttle response
- Electric starting facilitates quicker
stall recovery and lowers rider fatigue
- Large-volume airbox contributes to both
intake efficiency and the sharp engine
response. An air duct fashioned from polyethylene
(known for its ability to resist deformation
caused by intake pulses) helps ensure
stable engine performance
- Torque delivery is tuned to match the
rear tires’ ability to deliver traction,
making it easier to accelerate without
excessive wheelspin. Efforts were made
to achieve the widest possible torque
curve, so that traction can be maximised
through a greater part of the rev range
- Asymmetrical high-acceleration cams
yield high intake efficiency
|
| Digital Fuel Injection |
- 32-bit digital fuel injection system
uses a 42mm throttle body. This system
measures coolant temperature, air intake
temperature, air intake pressure, engine
speed and throttle position, then automatically
delivers the ideal amount of fuel to optimize
power delivery
- Crisp engine response is especially
advantageous for instant acceleration
after landing jumps
- Fuel injection also provides trouble-free
starting – a great benefit in races
where riders line up with their engines
off and need to start their engines before
being able to blast away from the starting
line
- Fuel injection allows the use of a lighter
throttle return spring. This helps reduce
rider fatigue, because less pressure is
required at the throttle lever
|
| Transmission |
- The five-speed (one-down, four-up) manual
transmission locates the reverse gear
below first. Actuating the reverse-lock
release lever when in first gear allows
you to shift “down” into reverse
- Compact reverse-lock release lever can
be activated with the right thumb, allowing
the reverse gear to be engaged while still
keeping the front brake lever depressed
- The combined weight of the reverse gear
system and the lightweight aluminium chassis
is no heavier than using a steel frame
without reverse
|
| Aluminum Chassis |
- Highly rigid aluminum frame contributes
to the KFX’s excellent handling
and traction. The frame’s high torsional
rigidity enhances stability in corners
and allows the suspension to be easily
set up to suit course conditions
- Designed for high corner speeds, the
KFX ATV sits low to the ground, helping
to reduce roll tendencies
- Mounting the battery and coolant tank
in front of the engine lowers the center
of gravity, and helps weight the front
wheels for increased traction when cornering
- Single box-tube lower frame contains
the front A-arm attachment points. This
design is narrower than the competition’s
frames and enables the use of longer lower
A-arms
|
| Advanced Suspension Design
|
- Positive and negative suspension travel
enhances the front wheels’ ability
to stay in constant contact with the ground.
This helps maintain traction and steering
authority during hard acceleration and
in situations where the ground drops away
- Dual-rate front springs help deliver
progressive suspension travel to provide
excellent rough-surface handling
- Extra-long lower front A-arms help minimize
camber variations through the suspension
stroke, to maximize front wheel traction
and boost stability
- Motocross style rear shock features
both high and low-speed compression adjustability
as well as adjustable rebound damping
- Cast aluminum rear swingarm features
curved lines and rounded edges to help
disperse stress, as well as different
wall thickness for each surface, resulting
in a design that is both light and strong
- The swingarm’s high torsional
rigidity contributes to excellent rear
wheel traction
- The rear axle is tapered for reduced
unsprung weight
|
| Front and Rear Disc Brakes |
- Dual front hydraulic disc brakes offer
consistently strong stopping performance
- Petal-type rear brake rotor reduces
unsprung weight and helps clean the brake
pads for more efficient braking performance
in difficult conditions
- Integrated rear parking brake is designed
to be easily engaged and released while
wearing gloves. When engaged, the parking
brake lever also prevents the clutch lever
from being
actuated
|
| Additional Features |
- Two-tone seat features a smooth top
surface for excellent rider mobility and
slip-resistant sides for good grip when
hanging off in corners
- Seat, tank and side covers are shaped
to allow excellent rider mobility and
to provide support when hanging off in
corners.
- Tapered Renthal Fatbar offers both strength
and light weight
- Handlebar mount designed to accommodate
other MX-type handlebars, enabling riders
to select from numerous after-market styles
- Specially designed rear wheels feature
reinforcing plates for the rims. Located
on the axle side of the rims, these plates
reinforce the rims where strength is most
needed while minimizing weight
- Wide front bumper, can be gripped with
two hands to push/pull the ATV
- Two-piece “lapped” front
and rear fenders can be replaced separately
in the event they are damaged
- Detachable front headlight assembly
can easily be removed to reduce weight
when racing
- Optional kick-start system is available
for MX-style (GNC) races where light weight
is a priority
|
