KX design philosophy is simple: put mid- level to expert riders on the top step of the podium. This philosophy has not changed since the creation of the KX brand over
40 years ago. With 32 AMA SX titles to its credit, the most of any manufacturer, KX has a proven record of powering champions. Adding to its highly acclaimed engine and chassis performance, numerous industry firsts and advanced technology, fine-tuning for 2015 makes the new model the most potent KX450F yet.

Source: Kawasaki.

The 2015 Kawasaki KX450F’s slim aluminium perimeter frame is a lightweight construction composed of forged, extruded and cast parts. Chassis balance and settings were all set to suit race-experienced riders.

The centre of gravity and key dimensions (swingarm pivot, output sprocket and rear axle locations) were chosen so that the rear tyre would drive the bike forward (instead of causing it to squat).

The 2015 Kawasaki KX450F has adopted Showa’s SFF-Air TAC Fork with Triple Air Chamber, switching from the KYB air-fork featured on the previous model. The works-replica fork is very lightweight and highly rigid, contributing to superior riding stability. It comes with a high-pressure 300psi digital air pump provided with every purchase.

With settings chosen for high-level to expert riders, the new fork offers excellent shock absorption performance at high speeds, making it easier for racers to ride faster. Numerous other benefits include:
– High rigidity
– Very light weight
– Low friction
– Reduced heat influence from damping assembly
– Precise settings possible merely by changing air pressure – easy adjustability

To match, it now uses a revised, firmer, Showa shock absorber with the trademark Uni-Trak suspension system. It also features a larger 270mm oversize Braking front disc and 240mm rear.

The fuel-injected 449cm3 liquid-cooled, four-stroke single delivers hard-hitting power from low-through high-rpm. The broad powerband and responsive throttle offer a broad spread of torquey response that enables racers to get on the gas and go even from down low.

Race-inspired tuning and parts like the high-performance bridged-box bottom piston (a mass-production first when introduced on the 2010 KX450F) ensure top-level performance right out of the box.

For 2015, a revised piston crown and ECU settings result in an engine that pulls more strongly and spins up more quickly. Revised ECU settings include programming that enhances traction by retarding ignition when the rear wheel speed increases too quickly.

The revised piston crown increases the compression ratio (12.5:1 to 12.8:1), contributing to increased performance, and creates a modified squish area that promotes better air circulation for improved combustion efficiency.

The new shape is almost the same used on Kawasaki factory racers, and results in a stronger mid-range hit and stronger feeling at high-rpm and over-run. In general the engine feels lighter across the rev-range, and the engine pulls strongly after an up-shift.

Kawasaki’s DFI Couplers (Standard, Hard and Soft) are still utilised, allowing riders to change the fuel injection mapping in a matter of seconds to suit a variety of riding conditions. Easy access to the DFI coupler cap means no additional accessories are needed to alternate between pre-programmed maps.

It also has an optional KX FI Calibration Kit, which is the same kit used by Kawasaki’s works teams in the US. The kit enables expert riders to adjust engine characteristics (by rewriting actual data maps) to suit their preference, record riding data, and analyse their riding data to further fine-tune their settings.

The KX450F features a launch control system similar to that on their factory racers. With the simple press of a button, riders can activate a separate engine map designed to ensure efficient race starts in slippery conditions. The Launch Control Mode map retards ignition timing, allowing tyres to gain grip in low-traction situations, and allowing riders to focus on their lines.

Rib-less rear hub and butted spokes reduce unsprung weight, while lighter front and rear wheel axles save 31 grams and 32g, respectively. Thinner walls for the tubes of the rear frame (t2.0mm to t1.8mm) save approximately 50g in weight.

For 2015, green highlights on the suspension adjusters and engine oil cap and generator cover plugs contribute to a distinctive Kawasaki look.

Kawasaki Australia is yet to release information regarding pricing and the official release date.