01. Engine & Exhaust
Designed to churn out more torque than any 125 cc 2-Stroke engine to ever come before it, the 2023 KTM 125 XC is set to continue its dominance in its class with unrelenting forward momentum. With an overall engine weight of only 39.37 lb and impressive horsepower figures, this lightweight powerplant retains its typical high-revving character, while laying down the grunt where it matters most.
Pre-mix gets a remix across the 2-Stroke KTM XC range, with Electronic Fuel Injection setting the standard. Now there's no more jetting setup pre-race, and thanks to the all-new Keihin EFI, the ECU coming from Vitesco and reed valve case design, you can be guaranteed of laying down optimal power at any altitude, all of the time.
A 54 mm bore, highly innovative electronic exhaust port management, and a machined finish for accurate port timing means the cylinder on the KTM 125 XC does more than just house the piston. It results in much-improved rideability, engine control, and more adjustability of the engine characteristics, thanks to 2 selectable and distinguished engine maps. Also, it's auto-calibrating, meaning there's no more hassle with wrong power valve adjustments.
Connected to the cylinder head is a new radiator hose which features a visible water temperature sensor displaying the engine temperature at a glance for a quick understanding of the running condition of the KTM 125 XC. During servicing, accurate reassembly is guaranteed thanks to clear indication markings on the cast aluminium cylinder head.
An important update across the 2023 KTM XC range is an all-new 39 mm throttle body. Taking its learnings from the 4-strokes, 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 125 XC 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 new KTM 125 XC 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.
More compact but with added 'Braaap!', the header pipes on the 2023 KTM XC range provide exceptional ground clearance for when the going gets extra tricky, while a compact lightweight aluminum silencer provides the signature 2-Stroke soundtrack.
The KTM 125 XC features a revised (DS) Diaphragm Steel 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.