The crankshaft is specifically positioned to harness the rotating mass in the ideal centre of gravity, which creates a lightweight and agile handling feel. As such, the inertia produced by the crankshaft is carefully calculated to deliver optimal traction and rideability from the powerful 450 cc engine. A plain big end bearing comprising two force-fitted bearing shells ensure maximum reliability and durability, guaranteeing long service intervals of 90 hours.

Designed for optimised mass centralisation, the FC 450 crankcases arrange the shafts and engine internals in the perfect position to achieve the best possible handling. Manufactured using a high-pressure die-cast production process, the result is a thin, exceptionally strong wall thickness at the lowest possible weight.

The FC 450 features a dampened diaphragm steel (DDS) clutch that includes a single-diaphragm steel pressure plate instead of traditional coil springs. It integrates a damping system for better traction and durability. The clutch basket is a single-piece, CNC-machined steel component using thin steel liners, which ensures a compact overall engine design.

Produced by Pankl Racing Systems, the 5-speed gearbox is designed to be extremely light and durable while featuring optimised and proven motocross-specific gear ratios (29:72). Integrated into the shift drum, a Quickshifter sensor can be activated by pressing the QS marked button on the Map Select Switch to further aid smooth upshifting.

For 2025, the frame around the shock mount and steering head has less material, with revised wall thickness in higher stress areas improving overall strength. Together, these changes reduce the weight of the frame by 300 g for improved cornering, unparalleled rider feedback, and energy absorption. New engine mounts with cut-outs improve chassis flex characteristics, reduce weight, and contribute to confidence inspiring stability. The frame is finished with a premium metallic blue powder coating with frame protectors offering superior protection, durability, and grip in any condition.

Made from 60% polyamide and 40% aluminium, the two-piece subframe ensures exceptional strength and durability at an overall weight of just 1.8 kg. The lower subframe spars and frame mounts are manufactured from cast aluminium for significantly improved reliability. The upper section of the subframe is made from injection-moulded polyamide to enable specific flex characteristics and ensure a lightweight construction.

Working in unison with the frame design and suspension set-up, the CNC-machined triple clamps provide precisely calculated geometry for increased stability. Handlebar flex can be customised with the handlebar clamp, which offers two mounting options - rubber-damped for less vibration, or fixed for enhanced front-end feedback. The upper triple clamp is stiffer to ensure a smoother fork action and plays a vital role in the perfect alignment of the front wheel for superior handling.

The 48 mm WP XACT forks have been revised for 2025 to work with the new frame, reducing weight while providing more flex. Designed as a closed cartridge system, the forks have a capsulated, adjustable air spring and pressurised oil chamber for smooth action and consistent damping. Oil and air bypasses reduce pressure peaks and in combination with a mid-valve damping system, together with a hydrostop that applies a progressive damping force in the last 40 mm of travel, the forks provide precise feedback to the rider. The settings are easily adjusted via the single air pressure pre-load valve, as well as through easy access click adjusters for compression and rebound. A pump to adjust the air spring pressure is provided with each machine.

Revised for the updated frame and lower in weight, the WP XACT rear shock offers 293 mm of travel. Inside is a Computational Fluid Dynamics (CFD) optimised main piston for improved initial comfort that provides strong hold-up in all conditions. The linkage system also features updated, lower friction seals while a new linkage bolt saves weight. Rebound and high and low speed compression settings can be easily adjusted by hand to simplify any set-up changes.

The swingarm is manufactured using a die-cast production process for optimal rigidity. To optimise and match the flex characteristics of the new chassis, a 22 mm rear axle is utilised. Additionally, the revised chain slider offers improved durability while the chain guide is designed to be less prone to catching on external objects.

A stiffer, one-piece airbox design with an optimised air intake reduces air deformation, ensuring an unrestricted flow of air and maximum filter protection. The Twin Air filter is easily accessed without tools, by simply removing the left side panel for easy maintenance.

The high-performance Brembo hydraulic clutch system guarantees even wear, near maintenance-free operation, and perfect action in every condition. With this hydraulic system, free play is constantly compensated so that the pressure point, and function of the clutch remain identical in cold or hot conditions, as well as over time. Countless hours of race-focused testing have proven the high-quality, Italian-made Brembo hydraulic systems' exceptional reliability.

The highest level of quality is guaranteed as the class leading Brembo brake calipers are made from single-piece aluminium for exceptional strength at the lowest possible weight. Together with a 260 mm front and a 220 mm rear disc, which are designed to prevent mud build-up, superior stopping power and braking confidence is guaranteed in all conditions. For 2025, a new, stronger rear brake pedal offers improved durability for continued braking performance.

Developed between Husqvarna Motorcycles and leading handlebar manufacturer ProTaper, the exclusive bend offers superior comfort, class-leading strength, and fatigue resistance at the lowest possible weight.

ODI lock-on grips feature an innovative, integrated throttle mechanism and are installed without using glue. The throttle assembly offers easy free-play adjustment with the option to fit alternative cams for a personalised throttle action.

The CFD-designed footrests are extra wide to ensure better control of the machine while at the same time are less susceptible to catching on deep ruts, take-offs when scrubbing, and trackside barriers. This is achieved by a narrower mounting design in the frame layout, which also helps reduce overall weight.

Assembled with CNC-machined hubs, lightweight spokes, and strong, black-anodised alloy rims by D.I.D, the wheels of the FC 450 offer strength and minimal unsprung weight. New, Dunlop Geomax MX34 Motocross tyres are fitted and feature a proven block-within-a-block design for enhanced control and superior grip on a variety of riding surfaces.

The exhaust system on the FC 450 features a flow-designed resonance chamber, which plays a vital role in delivering class-leading performance. Manufactured in two pieces and designed to be as compact as possible, the header pipe allows for the system to be removed without removing the rear shock. The silencer has a short and efficient design, moving weight closer to the centre of gravity and ensuring impressive power while keeping noise as low as possible. A black coating highlights the premium quality of the silencer.

Manufactured from high-strength aluminium, the radiators are designed using computational fluid dynamics (CFD) to channel air through them in the most effective way. A large centre tube through the frame reduces pressure at this point in the system for a consistent coolant flow while an internal thermostat further enhances reliability.

A 7.2 litre fuel tank integrates neatly with the ergonomic bodywork and features an updated rubber cushion beneath it to protect against wear from the frame. The one-piece fuel pump and integrated filter allows the tank to be emptied further to offer an extended running time. For improved durability, the external fuel line is specifically routed to make it less exposed and susceptible to damage.

The intuitive handlebar-mounted Map Select Switch allows riders to activate Launch and Traction Control, enable the Quickshifter, and allows riders to toggle between two engine maps. The easy-to-operate Map Select Switch allows racers to quickly alter and set up the engine characteristics on a race by race basis dependent on track conditions and rider preference.

The Quickshifter function can be activated or deactivated via the Map Select Switch and works by interrupting the ignition for a fraction of a second when upshifting. A sensor on the shift drum registers the force from the shift lever, sends a signal to the ECU, and ensures smooth gear changes - even when the throttle is fully open. To prevent unintended shifts and false neutrals, the function is only active from second gear upwards.

Traction Control on the FC 450 is engaged by pressing the button marked 'TC' on the Map Select Switch and functions by analysing throttle input from the rider and the rate at which engine RPM increases. If the RPM increases too quickly, the engine management system (EMS) registers a loss of grip and reduces the amount of power to the rear wheel to ensure maximum traction. This is a distinct advantage in wet or muddy conditions.

With the engine at idle, Launch Control is engaged by pressing the Traction Control and Quickshifter buttons simultaneously. Both symbols will start flashing to indicate that Launch Control is active. This function limits the amount of power to the rear wheel, improving traction, and preventing loss of control under hard acceleration. Once a gear change is made, the Launch Control will deactivate automatically. Additionally, the Quickshifter function is deactivated when Launch Control is engaged.

For personalised power delivery, the FC 450 has two built-in engine maps as standard. Map 1 (white) offers linear, predictable power, while map 2 (green) is more aggressive for a sharper throttle response and more explosive power output.

The engine management system (EMS) is designed to be small, light, and fast at processing data. It incorporates a rollover sensor (ROS) which cuts the ignition and shuts off the engine in the event of a severe crash for an additional layer of safety.

The hour meter comes with an integrated fuel level indicator, which is visible on the FI status LED, and warns the rider when the fuel level is getting low.

The combined start/stop switch is located on the right side of the handlebar for easy, thumb-operated use. Not only simplifying the starting and stopping of the engine, the removal of a designated stop only button from the handlebar reduces the risk of potential damage or activation in the event of a fall.

Along with the benefit of an easy electric starting system, a lightweight Li-Ion 2.0 Ah battery is fitted to the FC 450. The Li-Ion battery weighs approx. 1 kg less than a conventional lead battery meaning the convenience of electric starting is delivered while keeping overall weight to a minimum.