If maximum power is required, there is no other way but the 450 SX-F. This model has proven itself in the main championships around the world over the years. Thanks to its compact SOHC (single overhead camshaft) engine that delivers explosive but controllable power, it is the weapon of choice for the US KTM Factory Team and Ryan Dungey winning the AMA Supercross championship 2015.
Features May Include:The new frame design provides approximately 20 % higher torsional rigidity and 30 % less longitudinal stiffness, with newly designed engine stays for less vibration. This increased flexibility results in better absorption of the energy created from the front and rear wheel loads supporting the suspension for more comfort and less rider fatigue. A 0.4° steeper steering angle and a 10 mm shorter wheel base contribute to better handling and last but not least it´s around 380 g lighter than the previous model.
As on the predecessor models, the new SX generation features a reworked cast aluminium swingarm. The updated design offers reduced weight and an optimized flex behavior supporting the frame and suspension created with a single-component casting process. The weight reduction is 250 grams.
The new generation of monoshock made by WP Suspension has been developed for the new SX models in conjunction with the new frame and swingarm architecture, including the reworked linkage system and the new WP forks. The linkage system has also been reworked with a revised geometry and longer pull rods, which was tested last season in most of the KTM factory bikes.
The KTM SX models are fitted with a revolutionary new and super-lightweight WP fork, a 48 mm USD air-sprung fork developed by WP Suspension in close collaboration with KTM. It is a split fork with separate functions for each fork leg. The damping functions are on the right side, whereas the air spring is in the left. The left leg features a capsuled air cartridge. This air spring is easy to adjust to any rider weight via a single air valve and a standard fork air pump. The right fork leg integrates a completely new damping cartridge to fit single damping leg requirements, and the damping can be adjusted to the track conditions or the rider’s preferences with a twist of a dial. The new fork with approximately 300 mm travel has outstanding response and excellent, very consistent damping characteristics, while also with a reduced weight of 1.4 kg compared to its predecessor.
With new features such as its much more compact dimensions, stronger performance throughout the rev range and a weight reduction of 1.8 kg, this newly developed powerplant is the lightest 450 engine on the MX market. With a reworked single overhead camshaft cylinder head and the latest electronic fuel injection, it is distinguished by unrivalled power of more than 62 hp and a highly efficient power delivery.
The 450 SX-F’s crankshaft features 10 % more inertia (without increasing weight) and utilizes a shorter connecting rod over the previous model, which contributes to an overall compact and light engine with a snappy power delivery. A higher balancing factor reduces the vibration level. A plain big end bearing with two force-fitted bearing shells runs directly on the crank pin, and the oil feed for this is ensured by the engine’s pressure lubrication. An overall design that offers the customer lengthened service intervals.
Like all KTM 4-stroke motorcycles, the 450 SX-F is started with ease by pushing a button. Especially in the heat of a motocross battle, as demonstrated time and time again, an electric starter can become an invaluable advantage.