Yamaha Motor Australia have announced the all-new Yamaha WR450F and we like what we see. Celebrating it’s 20th year in production, the ground-up revision of the WR has brought the bike much closer to the YZ450F, like the original 1999 WR450F, which was based of the ’99 YZ.
So what’s new? Pretty much everything!
ENGINE
Engine based on the cutting edge YZ450F
The power unit is based on the current YZ450F engine but with specific enduro settings. The reverse fed, mass centralised layout and specifications are the same as the YZ450F engine, but the intake and exhaust systems, fuel injection and ignition advance maps are tuned to provide the fast enduro rider with stronger and longer-lasting pulling power at high rpm.
Free flow air filter contributes to linear response
The filter element features reduced airflow resistance with increased reliability. The new filter and the length of the intake funnel contribute to an excellent feeling of traction and linear characteristics during acceleration and deceleration. A model-specific muffler design is also adopted. And adding rubber seals to the centre positioning pin increases its dust-filtering capability.
Lighter, tougher clutch
The new WR450F’s clutch adopts the same spec as the 2019 YZ450FX. In order to better handle harsh enduro conditions, a highly heat-resistant friction plate is specced. Also, a new design that eliminates the judder spring is adopted for a lighter clutch lever pull and greater reliability
Wide‐ratio 5‐speed transmission
The new WR450F adopts a wide-ratio 5-speed transmission with the same spec and same gear ratios as the 2019 model YZ450FX. This provides both good off-road performance to clear difficult and technical areas as well as high-speed performance for flat dirt sections. Also, the shapes of the dog gears have been revised.
Mass centralised starter system
A lightweight starter motor contributes to mass centralisation. Also, a garter spring is adopted for the spring of the one-way clutch in order to reduce horsepower loss – a 60% reduction in load compared to the outgoing model. The kick starter is now an optional accessory part that has been eliminated to save weight.
New smartphone tuning
On board WiFi means that you can tune the new WR450F to different track conditions using your smartphone. The new Power Tuner app allows you to make fueling and ignition timing changes instantly and upload/share them for the ultimate in track-side tuning.
The free Yamaha Power app also allows owners to record race log information and monitor a range of data such as maintenance and system diagnosis, engine run time and more.
Engine map switch
A bar-mounted dual engine map switch has been adopted and positioned next to the left lever to enable changes in the engine power delivery characteristics mid-race. This switch allows the rider to select one of two engine maps on the fly at the press of a button to cater for changes in the riding environment.
CHASSIS
Sharp handling YZ450F bilateral beam frame
WR450F now runs the same bilateral beam frame as the current model YZ450F. To achieve a rigidity balance with the amount of flex needed for enduro riding, the fastening torque of the front engine mount brackets has been altered to fine-tune the rigidity. The upper-side mounts are the same as on the YZ450F, while two-plate type mounts are used for the front-side mounts. These tuning changes are the same as on the 2019 YZ450FX.
The result contributes to the machine’s excellent feeling of contact with the ground and offers feedback about the riding surface while providing a light feel to the handling.
Industry leading front and rear suspension
WR450F runs the same KYB air-oil-separate upside-down front fork as the YZ450F but with model-specific enduro settings to provide stable damping force. This suspension is acknowledged to be the best available on a production dirt bike and responds particularly well during the transition between the compression and rebound strokes.
The outer tubes are the same as the YZ450F and contribute to a secure feeling of ground contact. The diameter of the fork tubes has been increased compared to YZ450FX (24 mm to 25 mm) as has the flow rate of the fork oil. The mid-speed valve (MSV) that provides damping in the mid-speed range has been changed from a coil spring type to a leaf spring type. This mechanism responds to even the slightest amounts of oil flow and so delivers excellent damping feel at low speeds.
The rear shock absorber is also based on the YZ450F unit and features enduro model-specific settings. It features a coil with a higher fatigue strength than the current model’s and with an 11.5mm wire diameter achieves a weight reduction of approximately 350 grams. The capacity of the reservoir has been increased by 30cc to run cooler and achieve a more stable damping force.
More protective bashplate
The new WR450F features a more protective plastic resin engine guard to help prevent damage to the frame, engine, water pump and hoses when running through ruts or from impacts by kicked up rocks. Also, reducing the size of the open space at the front limits the amount of mud and stones entering and so reduces additional running weight.
Larger fuel tank
A newly designed 7.9-litre plastic resin fuel tank is featured that reduces the frequency of refueling during longer distances. The current YZ450F’s tank was used as the developmental base, and the lower portion has been extended toward the centre of the bike to improve mass centralisation, and to increase the tank’s capacity. A compact fuel pump is another new feature. These changes have made it possible to achieve a slim, compact body design comparable to the YZ450F that also results in minimum interference with the riding position.
New forged aluminium sidestand
A lighter and less obtrusive forged aluminium sidestand is positioned to ensure plenty of ground clearance when riding through ruts and the like. The new stand sits higher and the amount it juts out from the chassis is reduced which helps prevent snagging. The weight of the stand has also been reduced by about 100g. This is the same as the 2019 model YZ450FX stand design.
Sleek new headlight cowl
The WR450F’s new headlight cowl sits lower and closer to the rider. It contributes to centralisation of machine mass and helps to create a light, agile impression for the machine.
Lightweight speed sensor with high-precision display
A new lightweight front wheel speed sensor connects to a highly precise speed display and with no more speedo drive, makes front wheel changes easier. The system features a pulse wheel and sensor system known for excellent reliability and provides the detailed speed information essential for enduro riding.
Main features carried over from existing WR450F
• Rearward-slanted cylinder design featuring optimised weight distribution
• Wet sump lubrication
• Lightweight switch free starting system
• Large-capacity radiator (same as YZ450F) and cooling fan
• Lead battery resistant to effects of changes in ambient air temperature
• Headlight, LED tail light
• Speedometer, fuel level warning lamp, engine warning lamp