No production motocross bike has received as many year-over-year updates as the KTM 450 SX-F. Since 2012, the Austrian manufacturer’s “factory editions” have hinted at how future examples of this championship-winning machine will look in person and perform on the racetrack. They also satisfy AMA competition rules, which require producing a minimum of 400 units to meet stringent motocross and supercross homologation. The 2019 450 SX-F received a significant number of changes, most notably a cylinder head that is 15mm shorter and 500 grams lighter, new damping settings for the WP AER 48 fork and WP shock, and a revised steel frame that is now black in color and boasts a claimed 2-percent increase in longitudinal stiffness and a 10-percent increase in torsional stiffness.
During our racetrack testing, that increased frame stiffness was definitely felt and enabled the 450 SX-F to react far more quickly to rider input than in past years. The bike also cornered better and accelerated straighter, particularly in rough terrain. Further revisions include a new exhaust system, a stiffer upper triple clamp, redesigned radiators, fresh bodywork, and a different seat.
Likes: Neutral-handling chassis and improved ergonomics
Dislikes: Mellow bottom-end power delivery
Verdict: A good motocrosser in stock trim for vet riders
We rode the 2019 KTM 450 SX-F for the first time at Fox Raceway in Pala, California. The chassis changes were the most noticeable improvements over the previous-year model. The stiffer frame took away a little bit of rider comfort, but the bike handled more precisely.
The KTM 450 SX-F lives in the top-tier, premier-class motocross segment. The debut of the annual “factory edition” model in 2012 forced the Austrian manufacturer’s competition—namely Honda, Husqvarna, Kawasaki, Suzuki, and Yamaha—to work harder during the off-season to improve their machines even more dramatically every year.
The KTM is the lightest bike in the 450cc class with a fully fueled weight of 234 pounds and the second-most expensive at $9,899. It is one of only two 2019 450cc motocross bikes that is equipped with an air fork, the WP AER 48.