PREVIEW – 2023 Yamaha YZ450F

Words: Mike Ryan

Photos: Yamaha Motor Australia

Yamaha have unveiled details of their 2023-model YZ450F, with the brand's popular motocross machine said to be all-new for the coming year. Due for release in December, the MY23 YZ450F features a newly developed lightweight frame, lighter and more powerful engine, and all-new bodywork as well as adjustments and improvements in many other areas.

Yamaha say the starting point for their all-new YZ450F was the rider, with changes made to their long-running 450cc MX platform designed to meet the needs and expectations of the rider first.

Those needs aren’t focussed on those at the elite level, with consideration given to riders of different skill levels before any changes were implemented.

Engine

Although the 2023 YZ450F retains the backwards canted 450cc single-cylinder engine that was introduced for 2010, that powerplant has undergone what Yamaha says is a total redesign, delivering more power in a more linear fashion, while reducing weight, cutting down on size and centralising the rotating mass.

The cylinder head and forged aluminium piston are lighter and newly designed, as is the con rod and crank assembly, while plain bearings replace needle roller bearings. There’s a new timing chain and tensioner, a new high-precision, low-friction cam chain and a single balancer weight that features a new hollow balancer shaft to reduce vibration.

Intake and exhaust ports are reshaped, with larger 39mm titanium intake valves introduced that increase air intake volume by a claimed 9 per cent at maximum lift. These changes are in harmony with a completely new intake path that funnels fresh air into the front-feed airbox through space between the frame, seat, sidecovers and fuel tank; a design that also limits water and dirt ingress.

The airbox itself has been redesigned (part of a narrower cross section), creating a vortex to separate dust from incoming air before it hits the filter, which is new, too, now in a round design instead of the current YZ450F’s square filter.

Additionally, the cooling system has been updated, while the switch from dry sump to wet sump lubrication contributes to the MY23 bike’s weight reduction.

Overall, the engine changes have resulted in a claimed 5 per cent more power and a redline that’s 500rpm higher for more top-end power.

Transmission

A five-speed transmission remains on the MY23 YZ450F, but it’s been redesigned in harmony with the engine changes, while also being being stronger and lighter.

A wider distance between the vertically-stacked driveshafts has been achieved by moving the centre shaft up, with wider diameter gears added, too.

The clutch remains cable-operated, unlike the hydraulic units offered by Honda, Kawasaki and KTM, but the plate is now a 1-piece steel unit, instead of the previous 2-piece steel/aluminium design, with a conical spring in place of coil springs. This redesign shaves 0.75kg in weight and delivers a claimed lighter lever pull and more direct feel.

There’s a new look to the clutch cover, too, with a geometric pattern incorporated into the design.

Frame

As with the engine and transmission, the 2023 YZ450F’s frame is broadly similar to that of the current model at first glance, but has been completely redesigned.

Still of bilateral beam configuration and aluminium construction, the all-new frame has been subject to changes in the location of key elements, as well as geometry, rigidity and weight.

Yamaha says significant changes for the 2023 YZ450F frame include a 15mm lower joint between the tank rails and head pipe, with the tubing that connects the tank rails to the downtube lowered by the same amount. The downtube itself is more rigid, as is the cross tube and swingarm pivot point.

Additionally, the front engine mount is now a thinner steel item with three through bolts, replacing the thicker aluminium item that uses a single bolt.

The new frame is part of an overall weight reduction that’s been achieved through lightweighting of many other elements, like the footpeg brackets, generator and even the throttle cable. The result is that the MY23 YZ450F tips the scales at 109kg wet – 2.3kg lighter than the current model.

Plastics

Under the banner of ‘horizontal movement,’ the all-new bodywork on the MY23 YZ450F delivers what Yamaha call a seamless and rounded finish to the plastics, allowing for more rapid shifting of body weight on the track.

The new airbox feed path allows for the removal of front air ducts, in turn allowing for more compact radiator shrouds to be fitted. Combined with a narrower fuel tank, overall width in the centre section has been reduced by 50mm.

Shorter mudguards front and rear are part of a shorter front-to-rear length overall, while the sidecovers are new and the fork guards are longer. In fact, none of the plastics on the 2023 YZ450F are carried over from the current model.

The seat is higher by 5mm and flatter in profile, too, but reprofiling the sides with rounded edges allows for easier lateral body movement.

Footpegs have been lowered 5mm, with the four-position adjustable handlebars moved, too, giving what Yamaha says is the ideal position for riders of various physiques. This should address criticism of the YZ450F's ergonomics that have come from some quarters in the past.

Suspension and Brakes

KYB suspension carries over for the 2023 YZ450F, but the valving front and rear is new to suit the new frame, offering improved bump absorption and increased levels of traction.

Being able to make front-end compression adjustments by hand - without tools - is also new, while Yamaha’s Power Tuner app addresses suspension FAQs with recommendations on settings to suit different riding styles and track conditions.

In terms of the brakes, the front and rear ventilated discs carry over, 270mm font and 240mm rear, as do the Nissin calipers and most of the other componentry, but there is a new rear brake hose that’s more flexible to improve response to rear brake application and allow the kind of accurate braking control that’s important in motocross.

Traction and Launch Control

Both the Traction and Launch Control systems on the YZ450F are new for 2023, starting with the Traction Control, which now has ‘High,’ ‘Low’ and ‘Off’ settings that adjust the level of intervention based on rear wheel slip that’s measured by the bike’s ECU.

The Launch Control adds an rpm limiter that’s adjustable in 500rpm increments from 6,000rpm to 11,000rpm to suit different surface and weather conditions. The system is also smart enough to recognise when a race start has been completed and automatically disengages the rev limiter, with Launch Control itself deactivated entirely when third gear is reached.

Both Traction and Launch Control functions are adjustable through the Power Tuner app, which now makes altering the engine mapping easier, too. A new ‘Quick Tuning’ function allows simple mapping adjustments, from ‘smooth’ to ‘aggressive’, via a slide bar.

Guides for suspension and engine tuning are also included in the Power Tuner app, with another new feature for 2023 being a Lap Timer that records rpm, fuel consumption, speed and other data.

Coming Soon

Release of the 2023 Yamaha YZ450F has been confirmed for December, 2022, with pricing from $14,499 incl. GST.

One colour will be available – Team Yamaha Blue – with new-for-2023 graphics. The Monster Energy Yamaha Racing version that was offered this year seems to be off the table for now, although it will be offered in some other markets.

Other Models Hold Steady

There are no changes for Yamaha’s 250cc, 125cc, 85cc and 65cc MXers for 2023 beyond new graphics in the style of those on the MY23 YZ450F. Same goes for the WR450F and WR250F, which only receive cosmetic changes for the coming year.

No mention is made of the YZ450FX and YZ250FX, nor the YZ250X and YZ125X two-strokes in the MY23 model information released in August, so the future of these models in the Yamaha lineup is unknown at time of writing.

See your Yamaha dealer for more details.