Ant Lyon•29 Aug 2011

REVIEW

Launch: 2012 Kawasaki KX450F

Has Team Green just released the most amenable motocross weapon ever, with just about everything adjustable on the company's open class flagship?

WHAT WE LIKE

Adjustable ergos
Launch control
Plug 'n' play power<LILAUNCH control LI power< play ?n?

NOT SO MUCH

Engine case paint wears quickly
Beefier clutch springs mean heavier lever pull
Flimsy plastics

Year after year, the pursuit of competition and media shootout wins propel the “big five” motocross bike manufacturers to new heights of engine and chassis performance. The old formula “what wins on Sunday sells on Monday” is still as true as it ever was, which is why Kawasaki’s fully overhauled 2012 KX450F is perhaps the most surprising motocross offering of the last decade.

Sure it’s a faster, slimmer, better suspended, slicker-handling machine than its predecessor with the usual set of engine refinements (new piston, cam and exhaust), but the real triumph is that Kawasaki’s managed to shake off the performance tunnel vision and create the most universal bike to ever turn a knob in anger.

Doesn’t matter whether you’re short, tall, fast or slow, the 2012 KX450F can be customised to your proportions and talent. Four optional handlebar positions (courtesy of reversible bar clamps and two optional mounting positions in the top triple clamp) lets you find the most comfortable cockpit arrangement, while a second 5mm lower footpeg position is perfect for the lanky-limbed among us.

Visit the 2012 Kawasaki KX450F in Bike Showroom

At 189cm tall, I found a degree of comfort I’ve never experienced before on an open class motocross weapon by choosing the lower peg position coupled with the bars mounted in the forward triple clamp holes and with the bar clamps reversed.

Not only did the configuration save me energy when moving from a seated to a standing position, it also gave more room to get my inside leg up underneath the bars when hooking through ruts. In flat corners the bar position was particularly good as it puts you more on top of the bike, increasing control on the skatey sections of the track. These cockpit options alone make the KX-F brilliant value for money, as until now customising your layout was only possible with expensive aftermarket triple clamps and pegs.

Complementing the new ergos is a 4mm narrower frame, flatter seat/tank junction and sleeker plastics which let the KX-F finally shed its reputation as the porkiest bike in class. On paper it’s a subtle change, but on the track the KX-F feels smaller, nimbler and easier to move around on and you'd swear it was lighter (even though it isn't).

2008 Australian Pro Lites champion Luke George was on location at the Australian KX450F launch and was quick to sing its praises.

“As soon as I'd done the first lap I liked what I was on. Kawasaki 450s have always been good in a straight line, but they've struggled a bit in the turns. I think they've fixed that now with the new bike.

“The more streamlined chassis makes it feel lighter and gives the KX-F awesome turning characteristics, whether you're tackling flat corners, ruts, or slippery off-cambers. I also really like it in the air over both small and big jumps -- it's predictable and stable, but also light and flickable.”

MAPPING IT OUT

The next port ‘o’ call of customisation comes via the three interchangeable ignition maps. By simply plugging in a different coupler on the right of the steering head, the formidable 449cc DOHC powerhouse instantly goes from pussy cat to killer.

Designed to smooth the power output for slippery track conditions, the soft map also doubles as the perfect beginner map for riders either not experienced or fit enough to hang on to the more aggressive settings. With the standard map coupler in place the KX-F produces a stronger bottom end hit than the 2011 model and keeps pulling right through to its blistering top-end overrev.

With a twist of the wrist the big Kawi will hurl you out of corners and over obstacles without bouncing a valve and is more than enough to satisfy all but the highest level pilots. Dial up the aggro map and be warned -- with brutal, neck-snapping throttle response and huge horsepower, the KX450F in this trim is an animal that will bite the inexperienced!

Factory Kawasaki rider Billy Mackenzie is used to the best machinery money can buy and prefers a power delivery with Mike Tyson-like punch. “It has the response of my 2011 race bike, but without the extra power gains,” said the Scot, who was optimistic about what the new bike will become under a factory mechanic's spanner. “It's got the potential to be just as powerful as our Pro Circuit motors and, once we start putting pipes on it and working the heads, it's going to be one of the better bikes in the field.”

LAUNCH CONTROL

Kawasaki has also included a button-operated ‘launch control’ system which works in concert with the ECU by activating a smoother traction map that helps reduce unnecessary wheel spin on race starts. Once off the line and in front of the pack, the full power of the engine is restored again as the rider selects third gear. Does it work? Absolutely. Is it for everyone? Maybe not. While club level riders will love its forgiving nature and get better starts than ever, more experienced riders may find it a disadvantage as it takes some control out of their hands.

“On a grippy start where a pro needs to control the power, it'd actually be a disadvantage as the bike's such a great starter without it,” said George, before adding that in certain conditions even the pros might benefit from it. “Even though I'm a good starter I think the launch control would help me on a dusty or slippery start, and once I got used to it on concrete I think it would be awesome there, too.”

According to George, it's the lesser rider that will revel in the system the most. “For a guy whose start technique isn't there, the Launch Control system is the best thing ever invented,” enthused George. “They can pretty much hold it pinned and dump the clutch and it's not going to loop out. It'll let them get a good start up there with any Pro, even though they're not as talented.”

SUSPENDED MOTION

The suspension spring rates and valving is on the money for riders between 70-85kg, but those 90kg and upwards would benefit from one rate heavier springs and some heavier valving. Initially the silky smooth DLC-coated fork handled fine through corners, but dove on corner entries and blew through the stroke on harsh braking bumps and heavy landings.

At the rear the shock also clunked hard on our heavier riders, especially while tripling through the large rolling whoops.

To fix it we went nine clicks harder than standard at both ends and slid the fork through the triple clamps 5mm to raise the front end. This made a huge difference, improving bottoming resistance, levelling out the bike under braking and making it more stable coming into corners.

With the shock sag set at the recommended 104mm and a few clicks harder on both compression and rebound, we were able to get the KX-F to performed admirably around the jump-laden and deeply rutted Appin circuit.

Visually, the KX-F has come in for a big upgrade which improves its eye candy factor when cruising into the pits. However, the changes aren't just for show. Huge FMX grab-hole sized vents in the airbox let air flow freely into the engine, while the redesigned radiator shrouds -- which are still cheap and easily broken -- no longer catch on your boots. The brakes are still strong and progressive and one finger is more than enough to pull you up eye-bulgingly quick.

Kawasaki hasn't just created a race winner, it’s made the Volkswagen of motocross bikes: a machine for the masses with a breadth of appeal other manufacturers will struggle to match.

Tall riders or short, A-grade or beginner, the KX-F can be customised to accommodate just about anyone and you don't have to be a brain surgeon to do the adjustments yourself.

It's a bike born to destroy motocross tracks, but also one you could race (and win) a supercross on straight out of the box. Just fit the aggressive map and a bigger rear sprocket to get you over those jumps straight out of corners, bolt in some heavier springs and you have a bike capable of taking it to the race teams.

SPECS: 2012 KAWASAKI KX450F

ENGINE

Type: Liquid-cooled, DOHC, four-valve single cylinder

Capacity: 449cc

Bore x stroke: 96.0mm x 62.1mm

Compression ratio: 12:5.1

Fuel system: Electronic fuel injection

Claimed maximum power: Not given

Claimed maximum torque: Not given

TRANSMISSION

Type: Five-speed

Final drive: Chain

Clutch: Wet

CHASSIS AND RUNNING GEAR

Frame type: Aluminium perimeter

Front suspension: 48mm USD fork with rebound and compression adjustment, 314mm travel

Rear suspension: Uni-trak with rebound and compression adjustment, 315mm travel

Front brakes: 250mm petal disc with dual-piston caliper

Rear brake: 240mm petal disc with single-piston caliper

Wheels: Wire spoked

Tyres: Bridgestone 403/404 -- front 80/100-21, rear 120/80-19

DIMENSIONS AND CAPACITIES

Rake: 26.9 degrees

Trail: 113mm

Claimed wet weight: 113kg

Seat height: 955mm

Wheelbase: 1480mm

Fuel capacity: 6.2 litres

OTHER STUFF

Price: $11,999

Colour: Lime green

Bike supplied by: Kawasaki Australia, www.kawasaki.com.au

Warranty: None

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