2012 Japanese 450cc motocross wrap

The 2012 range of 450cc motocross bikes is amazing, as there’s just so much performance and technology encased in the svelte, 110kg packages. That was clearly evident after a recent outing at the Mount Kembla (NSW) motocross track, which was set aside as a ‘Japanese-only day’ for the Bikesales Network to sample the latest offerings from the Orient.

Initially, all four bikes proved to be a handful on the hard-pack slippery surface, but as the day wore on and the track turned tacky, we were able to ‘lock in’ their relative strengths and weaknesses  – well, minor shortcomings is probably a better description – of the snarling four-strokes as we reeled off lap after lap.

But here’s the executive summary – this quartet has more than enough personality to satisfy what you’re looking for in a 450cc motocrosser, whether it’s the brute horsepower of the Kawasaki, the sharp and accurate handling of the Honda, the all-round package of the Suzuki, or the futuristic engine configuration of the Yamaha.

Honda struggled in previous years to come up with a bike that was well balanced and comfortable to ride on, with a lot of riders changing rake angles and rear ride heights by spending up big on aftermarket parts.

However, in 2012, Honda has not only sorted out its problem and matched the rest of the brands, but has actually jumped ahead with a machine that rides like it’s on rails.

Honda has achieved this by balancing the chassis around the engine. This bike really is a dream to ride. It’s no wonder Chad Reed decided to race a Honda when he went it alone (Ed: and Ben Townley has just destroyed the field on one in the opening round of the 2012 MX Nationals in Australia) because it just does everything you require from it with very little effort.

You can turn the bike down on an up-ramp, and you can scrub, whip and even land while steering the bike into those tight inside lines that can sometimes be quite hard to traverse on a big 450. It feels like a very small 450, which is a great thing for when you don’t feel like getting pounded around a motocross track by an arm-tearing rocketship.

The only disappointing thing about the CRF450R is that the company’s seemingly spent as much time on getting the bike to handle as it did on making the bike quiet. It sounds really muffled; like it wants to bark but something is holding it back.

Honda has built a massive exhaust pipe with the smallest little hole in the end of it, and also fully enclosed the airbox to get the machine to come under the FIM noise limit. But all this unfortunately holds back the real power the CRF450R has inside. I would have personally liked to have bolted on an aftermarket exhaust and opened up the airbox to see what it really had to offer.

SPECS: 2012 HONDA CRF450R
Engine: Liquid-cooled, SOHC, single-cylinder, four-valve four-stroke
Displacement: 449.7cc
Bore x stroke: 96.0 x 62.1mm
Fuel supply: PGM-F1 electronic fuel injection
Transmission: Five-speed
Fork: 48mm KYB upside-down, 310mm travel
Shock: Pro-Link with KYB damper, 315mm travel
Fuel capacity: 5.7 litres
Claimed wet weight: 108.9kg
Colour: Red
Price: $11,490

Kawasaki has put a big effort into R & D for 2012, and it’s clearly obvious. The end result is a rocketship that can be altered to suit individual riding styles with its adjustable footpegs and bar mounts, as well as the three different mapping plugs that can be swapped over in a matter of moments to produce power pulses anywhere from mild to wild.

The all-new chassis has changed the characteristics of the bike dramatically. Instead of being coaxed into a relaxed seated riding position behind the handlebars like on the 2011 model, the 2012 model now sits you up over the handlebars, giving you more control and a better feel over the front end of the bike.

In concert with the chassis comes a new set of stylish plastics which don’t only just add to the aggressive look of the new KX, but also make the bike feel narrower and more nimble between the rider’s legs.

The KX450F is the first production motocross bike to be released with a launch control button attached to the handlebars, which controls the amount of power transferred to the rear wheel without breaking traction.

The KX450F is the most universal bike of the bunch. It can be tuned to suit riders from tall to short, big to small, and even from expert to beginner without having to go out and spend up big on different sized bars, lower links or exhaust pipes. It has everything straight out of the box to allow a customer to shape the perfect ride, and for this reason the KX has to be right up the front as one of the class leaders.

SPECS: 2012 KAWASAKI KX450F
Engine: Liquid-cooled, DOHC, single-cylinder, four-valve four-stroke
Displacement: 449cc
Bore x stroke: 96.0 x 62.1mm
Fuel supply: Electronic fuel injection
Transmission: Five-speed
Fork: 48mm upside-down, 314mm travel
Shock: Unit-Trak, 315mm travel
Fuel capacity: 6.2 litres
Claimed wet weight: 113kg
Colour: Lime Green
Price: $11,999

R & D at Suzuki barely raised a sweat in 2011. That’s because changes to the 2012 RM-Z450 have only been cosmetic -- but I guess it was thinking along the lines of why change a good thing.

The Suzuki didn’t need any changing: it is already the most complete all-round package. From the engine right through to the suspension and chassis, this bike is perfect. It handles everything you can throw at it.

The suspension and chassis work well together. The bike steers without a problem and feels perfectly stable at speed. It has nice, big platform pegs which give the bike a solid feel, and the tank and seat are flat and thin to make the bike feel quite small. The cockpit has plenty of room to slide back and forth with very little effort.

The engine is very strong and has plenty of torque to pull you up and over all those big jumps with very little run-up. The mill actually works better if you short shift it and keep it in the meaty part of the rev range. If you are revving it right out then you are wasting the power. It’s virtually impossible to get this bike to bog or flat spot; the response is amazing.

You could pick up an RM-Z450 on the way to the races – I’m talking the same day -- without a problem. For this reason alone, the Suzuki would have to be one of my favourite bikes.

SPECS: 2012 SUZUKI RM-Z450
Engine: Liquid-cooled, DOHC, single-cylinder, four-valve four-stroke
Displacement: 449cc
Bore x stroke: 97 x 60.8mm
Fuel supply: Electronic fuel injection
Transmission: Five-speed
Fork: Upside-down
Shock: Monoshock
Fuel capacity: 6.2 litres
Claimed wet weight: 112kg
Colour: Yellow
Retail price: $11,590

The Yamaha is really unmatched when it comes to the amount of technology that has gone into developing it. The backwards facing engine, which is designed to minimise engine inertia over the bike’s steering, really makes sense once you ride it and realise how easy it is to throw around.

my biggest problem with this bike is its size. You definitely know you are riding a 450 when you are on it because of its sheer size. The main issue is the bulky airbox fitted underneath the petrol tank.

The power that pours out of the back of this thing is amazing. It really is a hard-hitting 450. There is no smoothness to the power: it is twist and go. For a rider like me who likes to get moving as soon as I touch the throttle it is great, but for others it can be quite intimidating.

The suspension works really well on the Yamaha. Almost without fail, I need to wind up the clickers or change spring rates to handle my weight, but the Yamaha is very forgiving.

I couldn’t throw my leg over the Yamaha without having a try of the Yamaha power tuner. I wanted to see if this thing was just a sales or the real thing, and let me tell you it works. Just to see how much, I got the Yamaha technicians to upload the most aggressive map and then the mellowest one to feel the difference. And to my surprise, the bike morphed from an arm-tearing monster into a tamed beast in no time.

For 2012, Yamaha worked on a major selling point -- reliability -- by revising the shift drum and shift fork design in the gearbox and upgrading the rubbers in the fuel tank and fuel pump to be able to stand up to the new E10 fuels. The suspension settings were also revised.

SPECS: 2012 YAMAHA YZ450F
Engine: Liquid-cooled, DOHC, single-cylinder, four-valve four-stroke
Displacement: 449.7cc
Bore x stroke: 97 x 60.8mm
Fuel supply: Keihin fuel injection, 44mm throttle body
Transmission: Five-speed
Fork: Kayaba, 310mm travel
Shock: Kayaba, 300mm travel
Fuel capacity: 6 litres
Claimed weight: 111.5kg (fully fuelled)
Colour: Blue or white
Retail price: $12,099 (blue model) $12,199 (white model)