The 2019 450 XC-F now comes with a newly designed resonator called Flow Design Header (FDH), a small chamber around the pipe that makes the front part of the exhaust slimmer and is devised to provide improved engine performance and less noise. The mufflers on the four-strokes have a new aluminum sleeve profile, new end cap, and a revised internal design. The muffler is now longer where it connects to the header pipe, which makes it easier to install and uninstall the exhaust system and eliminates the need to remove the shock when doing so.
The Keihin Engine Management System (EMS) has a new 44mm throttle body, a new seal for the Manifold Absolute Pressure (MAP) system designed to increase reliability, and a updated throttle cable mount to allow for smoother routing of the cables and to provide better access. The ECU also has new maps to work better with the new exhaust and cylinder head as well as optimize the traction control.
The XC-F bikes also come with a new lithium-ion starter battery designed to make the bike fire to life quicker, especially in colder conditions. The packaging of the voltage regulator and condenser has also been reworked in order to make the system more reliable, according to KTM. The final change made specifically to the XC-F machines are that they have three new brackets in the lower part of the frame to allow for an optional composite skid plate that can be purchased through KTM PowerParts.
The 450 XC-F has a newly developed, more compact cylinder head that is 15mm (approximately 0.6 inch) lower and 500 grams (approximately 1.1 pounds) lighter than the previous model. The cylinder head also has newly shaped ports, a new camshaft, and shorter valve timing designed to improve responsiveness. The cam chain guides are now made of a lower friction material as well.