01. Faster and wiser
Engineered to ensure class-leading performance and handling characteristics, all major engine components and shaft arrangements are carefully positioned closer to the centre of gravity to reduce the effects of rotational inertia. Tilted two degrees backwards to further centralise mass, the 250 cc 4-stroke engine is also 60 g lighter for 2023, tipping the scales at just over 57.3 lb. The FC 250 engine remains remarkably powerful with an increased power output and impressive torque to suit riders of all abilities.
DOHC cylinder head
Featuring finger followers treated with a Diamond-like Carbon (DLC) coating, the DOHC cylinder head is engineered for high-level performance and further refined for 2023 with multiple revisions to improve performance and durability. The titanium intake valves remain at 32.5 mm while the exhaust valves increase in size to 27.5 mm - a direct result of the new bore/stroke ratio, which in turn optimises gas flow. These revisions allow the FC 250 to rev freely and produce strong and efficient power throughout the rev range up to its 14,000 rpm limit.
Cylinder and piston
A new 81 mm bore houses a forged bridged-box-type piston made by CP, which weighs just 150 g. High strength aluminium is used to manufacture both the cylinder and piston, with both components professionally engineered for outstanding performance and reliability. The stroke has been adapted to 48.5 mm to match the resized cylinder, boosting the compression ratio to 14.5:1 and adding further torque and peak performance to the FC 250.
The FC 250 crankcases are designed to optimise mass centralisation by housing all internal components in the ideal position to achieve the perfect centre of gravity. 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 250 features a revised Diaphragm Steel (DS) clutch. Engineered from a single piece of CNC-machined steel, the redesigned clutch basket accommodates the new gearbox and allows the use of thin steel liners, which contribute to the compact design of the engine. Identical to the one used in the stronger FC 450, it is adapted perfectly to the new transmission ratio.
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 (24:72). A redesign of the shift shaft reduces the operating forces required for gear changes. Integrated into the shift drum, a new Quickshift sensor can be activated by pressing the QS marked button on the map select switch to further aid seamless upshifting.