2010 Yamaha YZ450F being put through its paces

This is the one we've been really looking forward to -- the press launch of the all-new fuel-injected Yamaha YZ450F.

The YZ450F has a unique design philosophy:  a rearward slanting engine with a straight intake tract mounted in a lightweight bilateral beam frame.

The air cleaner is now located where the tank once was, so the intake tract can have a straight shot into the cylinder head. The fuel tank is now living under the seat.

Yamaha claims the rearward slanting engine centralises mass towards the centre of the machine, giving the "engineers more freedom in locating the rear suspension".

Other claimed benefits of the forward-mounted intake include cooler intake air because it is unheated by the engine, and cleaner air, because the dirt and dust kicked up by the rear tyre is further away from the intake system.

We'll be talking a lot more about the YZ450F's technical platform in the full launch report next week, but in the meantime here's what the Bikesales Network's man on the spot, Shannon Warner, has to say about the bike, which is being launched at the Appin motocross track south of Sydney.

"Totally redesigned dike, loads of controllable grunt, and a funky engine management system that drastically changes the power delivery."

It sounds like Yamaha's hit the target: Shannon's certainly in a very happy place....

The new YZ450F is set to to throw down the gauntlet to its Japanese and European opposition, and has already strengthened those claims with victories in the US Open and the opening two nights of the Bercy Supercross in Paris, with the irrepressible James Stewart at the helm.

The 2010 YZ450F goes on sale next Monday for $12,099 (blue) and $12,199 (white) respectively, which is only a slight increase on the 2009 model -- a small price to pay for the massive technological leap.