With the 450 SX-F, the KTM range offers a winner bike that draws potential from a large-displacement engine and a chassis perfectly tuned to handling its raw power. Ryan Dungey has used it to win the AMA 450 Motocross Championship and saw absolutely no reason to change bikes in order to defend his title. No wonder, as the compact SOHC engine with the groundbreaking injection technology guarantees brute but highly controllable power. Among the large 4-strokes, the 450 SX-F scores mainly with its performance and agility. It is the right choice for every motocross rider looking for torque and power with lots of control for racing.
Features May Include:
The 450 SX-F's crankshaft employs a plain big end bearing. Two force-fitted bearing shells run directly on the crank pin. The necessary oil feed for this bearing is ensured by the engine's pressure lubrication. This design is a major prerequisite for the extremely high engine speed levels and unrivaled maximum power of the 450cc engine. Another decisive customer benefit is the crankshaft service interval which can be lengthened due to the plain bearing.
For 2014, KTM has optimized its gear tooth geometry to provide customers with a lightweight 5-speed gear box with increased durability.
The 450 SX-F employs the KTM-developed DDS (Damped Diaphragm Steel) clutch with a wear-free steel basket and extremely heat resistant clutch plates. This design is distinguished by employing a diaphragm spring instead of the usual coil springs, which makes for a considerably easier clutch action. Strengthened for 2013, the diaphragm spring also leaves sufficient space for a damping system integrated into the clutch hub, which benefits both traction and durability. A stronger inner hub further increases stability. The hydraulic Brembo clutch mechanism with a new master cylinder guarantees a light operation and highly controllable modulation of the clutch.
ENGINE MANAGEMENT SYSTEM (EMS)
In combination with the revolutionary injector position as developed by KTM, the Keihin Engine Management System, with electronic fuel injection and 44mm throttle body provides the engine with a spontaneous response and maximum performance. For 2014, the wiring harness of the 450 SX-F has been further simplified and even higher quality wires and connectors are used. In order to protect them against pressure washers, many connectors are now enclosed in new rubber boots. With an optional map-select switch from the KTM PowerParts program, EMS continues to allow selecting different engine characteristics. In addition, the optional User-Setting Tool allows to readout engine data with a laptop and change the ignition and injection mappings with a few mouse clicks.
COUNTER BALANCE SHAFT
The side-mounted counter balance shaft also drives the water pump. Thanks to the perfect mass balancing and the power plant's low total oscillating masses, engine vibrations can be kept to a minimum even at the highest engine speeds.
The die-cast crankcase has been further developed by removing the kickstart dome to achieve a weight reduction compared to its predecessor.
The compact 60hp power pack with a single overhead camshaft and the latest electronic fuel injection is distinguished by unrivaled performance and a highly efficient power delivery. Thanks to a revised crankcase, the weight is reduced for 2014.