The KTM 450 XC-F shares 95 percent of its parts with the Austrian manufacturer's flagship motocross bike—the 450 SX-F—including the same engine, suspension components, and chassis. The differences lie in the larger fuel tank, off-road-specific suspension settings, 18-inch rear wheel, kickstand, hand guards, and Dunlop AT81 tires. One additional part our testbike wore that does not come stock was the skid plate, which is available through KTM PowerParts.

2019 KTM 450 XC-F Engine

Before the shootout, we mounted a Dunlop D404 street tire on the rear wheel and ran the 2019 450 XC-F on our in-house Dynojet dynamometer, where it produced 52.12 hp at 9,530 rpm and 33.81 pound-feet of torque at 6,970 rpm. The KTM 450 XC-F ranks fourth in the horsepower department and second in torque—essentially identical to the Husqvarna FX 450 with a difference of only 0.22 hp and 0.13 pound-feet of torque. After the dyno pulls were complete, we fitted Dunlop AT81 tires, as we did on all of the bikes to ensure consistency in traction among them for the entirety of the test.

The 2019 KTM 450 XC-F’s power delivery is smooth from bottom to top and hits progressively harder the higher it gets in the rpm. It’s characterized by a somewhat mellow hit off the bottom, a plentiful midrange, and excellent top-end and over-rev. The KTM’s linear power delivery makes it easy to ride in all conditions—most notably tighter single-track. However, a harder-hitting bottom-end power would contribute to a lighter weight feel and would make it easier to get into the higher rpm without excessive use of the clutch. We also found that switching to the included optional black throttle cam got rid of the “chicken wing” feeling we had when holding the throttle wide open with the stock white throttle cam installed.

2019 KTM 450 XC-F in front of colorful field.
Weighing it at 240 pounds, the KTM 450 XC-F and Husqvarna FX 450 are the lightest bikes in the shootout.Jeff Allen

The KTM 450 XC-F is the second-quietest bike in the test—just a bit louder than the Husqvarna but still pleasantly quiet. The orange machine's power delivery is slightly more aggressive and quicker revving than the FX 450. It has a fair amount of engine-braking that is useful but not overpowering. The engine vibrates slightly, which is felt through the handlebar and footpegs. The Brembo hydraulic clutch works perfectly with its easy pull, and it does not fade under heavy use. It also helps the 450 XC-F's Pankl transmission shift smoothly and easily.

2019 KTM 450 XC-F Dyno chart.
The 450 XC-F produces 52.12 hp at 9,530 rpm and 33.81 pound-feet of torque at 6,970 rpm.Jeff Allen

The KTM 450 XC-F is the second-quietest bike in the test—just a bit louder than the Husqvarna but still pleasantly quiet. The orange machine’s power delivery is slightly more aggressive and quicker revving than the FX 450. It has a fair amount of engine-braking that is useful but not overpowering. The engine vibrates slightly, which is felt through the handlebar and footpegs. The Brembo hydraulic clutch works perfectly with its easy pull, and it does not fade under heavy use. It also helps the 450 XC-F’s Pankl transmission shift smoothly and easily.

The 450 XC-F has two maps that can be changed via a switch on the left side of the handlebar. It also has traction control, which can be used in either map. Map 1 (standard) has less low-end grunt than map 2 (aggressive), which pulls better off the bottom-end and has more of a torque feel. Map 2 was the preferred choice among test riders. Traction control made each map slightly less responsive and came in handy in tighter, more technical terrain.

2019 KTM 450 XC-F on dirt track.
The KTM’s power delivery is slightly more aggressive and quicker revving than the Husqvarna FX 450.Jeff Allen

2019 KTM 450 XC-F Suspension

The KTM's WP AER 48 air fork and WP shock are softer feeling than the Yamaha's and Honda's suspension. The components work well on slower to medium-speed areas with braking bumps, acceleration bumps, and smaller-sized trail obstacles. However, in faster-paced sections with larger-sized rollers and bigger impacts such as G-outs and jump landings, the suspension lacked some comfort and predictability in comparison to the Yamaha and Honda.

2019 KTM 450 XC-F jumping.
With a power delivery that is smooth from bottom to top, the KTM is easy to ride in all conditions—most notably on tighter single-track.Jeff Allen

The fork rides higher in the stroke than the two Japanese bikes and even with its softer overall feel, it offered good bottoming resistance. Test riders were happy with the fork’s stock 10.1-bar air pressure setting, but went in on rebound to alleviate its somewhat bouncy feel and to try to get it to ride deeper in the stroke. The shock felt especially soft. Going in on high-speed compression and slowing down rebound helped it hold up better and added more control when it got too low in the stroke.

2019 KTM 450 XC-F Chassis/Handling

The 2019 KTM 450 XC-F weighed in at 240 pounds on our automotive scales, which ties it with the Husqvarna as the lightest bike in the test. Despite that, neither Austrian machine feels quite as light as you would expect judging by its low reading on the scale, some of which has to do with the engine’s mellow bottom-end and smooth power delivery. Aside from the weight feel, the KTM is a neutral-handling bike with impressive cornering ability and good straight-line stability. However, it doesn’t corner as sharp as the Honda and is not as stable as the Yamaha. The chassis feels longer than the Japanese bikes as well.

2019 KTM 450 XC-F on dirt track.
The WP AER 48 fork and WP shock perform best on slower to medium-speed areas of the trail and track.Jeff Allen

The KTM 450 XC-F has a neutral stance with 105mm of shock sag and is easy to move around on with its narrow radiator shroud area and flat, comfortable seat. It’s also the narrowest bike from front to rear. The Neken handlebar has an agreeable bend and less rise than the ProTaper bar on the Husqvarna, so bar position isn’t as critical. The KTM’s Brembo brakes are the best in the class as they offer the most stopping power, yet retain a progressive and predictable feel at the lever. The ODI lock-on grips are a nice feature as well.

The 2019 450 XC-F comes stock with hand guards; it and the FX 450 are the only two bikes to come with them in stock trim, which test riders appreciated on bush-filled trails. We would like to see it come stock with a skid plate too, especially considering there are three brackets on the lower part of the frame to accommodate one.

2019 KTM 450 XC-F in boulders.
The KTM’s Brembo hydraulic clutch and Brembo brakes are the best in the class.Jeff Allen

Why It Should Have Won

It has a powerful yet easy to ride engine, a nimble-handling chassis, the strongest brakes, a hydraulic clutch, and is tied for the lightest bike in the test. It’s also pleasantly quiet.

Why It Didn’t Win

The WP AER 48 fork falls short of the performance of the stock suspension components on the Yamaha and Honda. Also, the engine lacks some bottom-end excitement and vibrates more than it should.