Yamaha's flagship off-road bike, the YZ450FX, returns for 2018 with minimal changes, including Dunlop MX3S tires (a switch from Dunlop AT81 rubbers), blue rims, and new graphics. The 2018 YZ450FX shares many of the same features as the previous-generation (2014-2017) YZ450F motocross bike, but with a few cross-country-specific features including a wide-ratio transmission, larger-capacity radiators, an 18-inch rear wheel, O-ring chain, skid plate, kickstand, off-road-specific suspension settings, and a different clutch setup comprising a different clutch plate material, springs, push lever, and oil valve. We took the YZ450FX out to the trails for a first impression of how the blue cross-country bike performs.

Engine

The YZ450FX engine has tons of power and lots of torque that work great in both high- and low-speed riding conditions. In tighter areas where the speeds are slower, the low first gear makes the engine very controllable and difficult to stall, but is understandably very short, making it only useful in tight single-track. Second gear is a bit more versatile and works best in moderately tight trails and areas that open up a little bit. Third gear works best for your average off-road course and, thanks to the engine’s plethora of torque, the bike can be lugged easily in third gear in most situations that aren’t too slow going. Fourth and fifth gear are best suited for more wide-open terrain when the speeds increase. The YZ450FX has a moderate amount of engine-braking but instantaneous throttle response. With those two qualities combined with how much torque it has, the bike is easy to ride and stay in control without exerting too much energy, which makes it easier to ride for a long period of time.

2018 Yamaha YZ450FX
Yamaha’s flagship off-road bike, the YZ450FX, returns for 2018 with a few minimal changes.Jeff Allen

Suspension

The KYB SSS fork and KYB shock that Yamaha has used for several years on its motocross and cross-country (off-road) bikes are still unbeatable in the comfort category. The KYB units soak up every impact, large or small, with an incredible amount of plushness, and even when you anticipate a jolting impact to your wrist and arms, the fork absorbs it as if it’s not even there and the same can be said for the shock as well. Being that the KYB components are set up more for off-road, they are understandably softer than the YZ-F motocross models, and both the front and rear do an excellent job of absorbing the impacts that come with riding off-road.

Updates for 2018 Yamaha YZ450FX
Updates for 2018 include Dunlop MX3S tires (a switch from Dunlop AT81 rubbers), blue rims, and new graphics.Jeff Allen

Chassis/Handling

The YZ450FX chassis has a larger overall feel when riding it, which is partially due to its wider radiator shrouds. It carries its 262-pound wet weight much better on the trail than it does when occasionally having to be lifted onto a bike stand. The instantaneous throttle response of the engine makes the YZ450FX feel lighter on the trail, and this is especially true when blipping the throttle to ride over obstacles, which the bike does with ease as a result of how stable and planted the chassis is. The planted feeling makes high-speed sections much less daunting, and as far as cornering, the blue bike favors being steered with the rear as front end traction is not as abundant as it is on other comparable bikes in the class.

2018 Yamaha YZ450FX
A wide-ratio transmission, off-road-specific suspension settings, larger-capacity radiators, and an 18-inch rear wheel are just a few of the YZ450FX’s cross-country features.Jeff Allen

Conclusion

The 2018 Yamaha YZ450FX is a potent off-road bike that has a plethora of power and torque, fantastic suspension, and a chassis that instills confidence at high speeds. It takes a little bit of time to get used its wider-feeling radiator shrouds, but once you’re accustomed to it, it has a very comfortable overall feel with its plush suspension, soft seat, and easy-to-ride, yet powerful engine. In addition to riding it in off-road conditions as it’s designed to be, we will be taking it to several riding areas including the motocross track because we feel it can handle it and prove to be a do-it-all bike for those who like to ride off-road and motocross.

KYB SSS fork and KYB shock that Yamaha has
The KYB SSS fork and KYB shock that Yamaha has used for several years on its motocross and off-road bikes are still unbeatable in the comfort category.Jeff Allen
torque of the engine
The torque of the engine combined with its wide-ratio transmission makes the bike easy to lug in tight situations.Jeff Allen
YZ450FX feel light on the trail
The instantaneous throttle response of the engine makes the YZ450FX feel light on the trail, and this is especially true when blipping the throttle to ride over obstacles.Jeff Allen
2018 Yamaha YZ450FX
The planted feel of the YZ450FX makes high-speed sections of the trail much less daunting.Jeff Allen
off-road conditions
In addition to riding it in off-road conditions as it’s designed to be, we will be taking the YZ450FX to several riding areas, including the motocross track because we feel it can handle it and prove to be a do-it-all bike.Jeff Allen

TECH SPEC

 
PRICE $8999
ENGINE 449cc, liquid-cooled, single-cylinder four-stroke
TRANSMISSION/FINAL DRIVE 5-speed/chain
MEASURED HORSEPOWER 50.5 hp @ 9250 rpm
MEASURED TORQUE 32.4 lb.-ft. @ 6940 rpm
FRAME Aluminum twin-spar
FRONT SUSPENSION KYB Speed-Sensitive System (SSS) coil-spring fork adjustable for rebound and compression damping; 12.2-in. travel
REAR SUSPENSION KYB shock adjustable for spring preload, rebound, and compression damping; 12.5-in. wheel travel
FRONT BRAKE Nissin single 270mm disc w/ twin-piston caliper
REAR BRAKE Nissin single 245mm disc
RAKE/TRAIL 26.3°/4.5 in.
WHEELBASE 57.7 in.
SEAT HEIGHT 38.0 in.
FUEL CAPACITY 2.0 gal.
MEASURED WEIGHT 262 lb. wet
AVAILABLE Now
CONTACT yamahamotorsports.com