CHASSIS TECH: 2019 vs 2018 Yamaha WR450F | Features
Yamaha overhauled the WR450F for 2019, making it lighter, narrower and more powerful. The chassis is based on the YZ450F and received a host of changes for MY2019.
Below is a side-by-side comparison of the 2018 and 2019 WR450F chassis.
IN MORE DETAIL
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.