2019 Yamaha YZ450FX First Look | 13 Fast Facts

June 7, 2018

2019 Yamaha YZ450FX First Look | Major Updates

Following in the footsteps of the major updates to the YZ450F motocrosser last year, the 2019 Yamaha YZ450FX off-road racer reaps the rewards of the experience gained by its track-focused brother.

With a new engine and chassis, the 2019 YZ450FX reminds us that it is serious about off-road competition.

1. From the transmission to the cylinder head, the 2019 YZ450FX’s motor is all-new. Rather than finessing an update, Yamaha made major changes to the 449cc powerplant.

2. The camshafts get new profiles. Yamaha says this give the motor “an ideal balance of 450cc class power with exceptional control and response.” It’s also matched to a new crankshaft.

3. The rearward-canted cylinder is now closer to vertical. To keep weight centralized, the cylinder has been pivoted forward a bit.

4. Continuing in the effort to centralize mass on the 2019 YZ450FX, the muffler is shorter. The wrap-around header is retained, while the muffler’s weight is now closer to the center of the motorcycle.

5. In yet another mass centralization effort, the electric starter has been updated. The starter motor is now more compact and has been moved. Also, the new lithium-ion battery is lighter, yet still high capacity—a must for GNCC competition.

6. The 2019 Yamaha YZ450FX’s new radiators have improved cooling. The core size is larger, and the angle has been adjusted to pick up more airflow. These two changes will keep the motor running at a lower temperature.

7. The Yamaha Power Tuner App has serious tuning and data acquisition capabilities. Using an app on your iOS or Android smartphone or tablet, you can tune the motor via a WiFi connection built into the Yamaha’s electronic system. Fuel and ignition mappings can be changed with the app. The app keeps track of your motor’s throttle position, rpm, coolant temperature and other parameters. Logging capabilities include your location, course conditions, and settings on your bike. Plus, the app keeps track of time between servicing of various components.

8. The transmission and clutch have been updated. There is a new outer pressure plate on the clutch, for a lighter clutch pull and increased durability. The wide-ratio tranny gets revised gears.

9. The twin-spar aluminum frame is all-new with a goal of more balanced behavior. The goal is more rigidity on three axes—lateral, horizontal, and vertical. Yamaha says this has been done “to provide an ideal balance between cornering feel and straight-line rigidity.”

To get there, the 2019 Yamaha YZ450FX gets new upper-frame bracing, new rear-frame spars, and updated engine mounts. Yamaha also notes that it is working “to improve contact to the ground and provide the best possible balance of stiffness for bump, rock and root absorption, as well as effortless cornering.”

10. To match the performance of the new frame, the 2019 Yamaha YZ450FX gets new suspension settings. The KYB SSS fork returns with larger pistons and updated valving. The KYB shock also gets new damping settings. The primary goal is better traction during cornering. As before, while the units are the same as the YZ450F, the YZ450FX damping is designed for success in GNCC and Hare Scrambles racing.

11. The KYB SSS fork has new fork lugs and axle brackets. This is being done to improve front-end feel and suspension action.

12. You will find updated seat and bodywork on the 2019 YZ450FX. The seat is narrower and lower, while the new bodywork is designed to increase knee grip.

13. The 2019 Yamaha YZ450FX will be available in dealers in July and will run $9499. That is a solid $500 increase over the 2018 edition, and $200 more than its motocross brother.

2019 Yamaha YZ450FX Specs

ENGINE

Type: 4-stroke single
Displacement: 449cc
Bore x stroke: 97.0 x 60.9mm
Compression ratio: 12.8:1
Valve train: DOHC w/ four titanium valves
Fuel delivery: Mikuni EFI w/ 44mm throttle body
Transmission: Wide ratio 5-speed
Clutch: Wet multiplate
Final drive: Chain

CHASSIS

Front suspension; travel: Fully adjustable inverted KYB Speed-Sensitive System fork; 12.2 inches
Rear suspension; travel: Linkage-assisted fully adjustable KYB shock; 12.5 inches
Tires: Dunlop Geomax MX3S
Front tire: 80/100 x 21
Rear tire: 120/80 x 18
Front brake: 270mm disc
Rear brake: 245mm disc

DIMENSIONS and CAPACITIES