01. Engine & Exhaust
The 2023 KTM 450 XC-F boasts one of the most manic 4-Stroke powerplants in the pits, with its SOHC engine proving to be the perfect example of advanced engineering. For 2023, the engine is tilted 2° backward with a lower sprocket position, which together with the benefits of mass centralization and reduced weight, makes the anti-squat behavior of the chassis second to none. With a massive peak power output and an overall engine weight of only 59 lb, you'll leave the competition with more than a little mud on the face.
The lightweight aluminum cylinder features a 95 mm bore and 63.40 mm stroke, housing a CP bridged-box-type piston weighing a meager 327 g. The piston features anodized annular grooves, adding durability and longer service intervals, with the compression ratio increased to 13.1:1 for added peak performance.
A completely redesigned SOHC cylinder head makes for a more compact and lightweight package, using a shorter profile with the camshaft located closer to the center of gravity. Lightweight valves are actuated via a DLC coated rocker arm with optimized timing, specifically designed to deliver precise levels of torque and throttle response. The diameter of the intake valves is 40 mm, while on the exhaust it is 33 mm. Redesigned intake ports allow higher flow coefficients, resulting in a more efficient and powerful engine, with a new valve cover reducing the number of mounting screws, and a single oil spray jet guarantees efficient cooling while keeping the weight low.
An important update across the 2023 KTM XC range is an all-new 44 mm throttle body. Taking its learnings from the KTM Factory Racing machines, the injectors are positioned in a double-injector pattern to ensure the most efficient flow into the combustion chamber, while the throttle cable is mounted directly without a throttle linkage providing smoother, uninhibited throttle action. This all adds up to cleaner, smoother fuel ignition, and more power without the fuss.
Designed with weight reduction and performance in mind, the crankshaft in the KTM 450 XC-F engine improves throttle response and contributes to the lightweight feel of the motorcycle. The perfect balance of rotating masses is achieved by balancing the weights of the crankshaft flywheel, the new rotor, and thanks to the innovative counter balancer shaft, engine vibration is kept to an absolute minimum.
The KTM 450 XC-F engine is designed with mass centralization and weight reduction as the main criteria. As a result, the crankcases have been designed to house the internal components of the engine in the perfect position to achieve an ideal center of gravity, while adding the least possible weight. The casings are manufactured using a high-pressure die-cast production process, resulting in thinner but more reliable wall thickness. And just to add a little extra - the KTM brand logo gives the black powder-coated engine cover the ultimate READY TO RACE look.
The KTM XC-F exhaust systems are expertly designed to deliver class-leading performance at the lowest possible weight. Featuring a flow-designed resonance chamber integrated into the 2-piece header pipe, the header pipe remains as compact as possible with the joining position allowing it to be removed without having to take out the rear shock. Further innovation allows for a short, lightweight aluminum silencer without increasing noise levels.
The KTM 450 XC-F features a DDS (Dampened Diaphragm Steel) clutch, which 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, which has been revised to accomodate the new gearbox in 2023, and continues to allow the use of thin steel liners that contribute to the compact design of the engine.