The 2020 KTM 125 SX is powered by a 124.8 cc liquid-cooled single-cylinder 2-stroke engine with Mikuni TMX 38 carburetor, kick start, 6-speed transmission, wet multi-disc DS clutch with Brembo hydraulics, and premix lubrication system delivering high-revving motocross performance and sharp throttle response. The chassis features a central double-cradle 25CrMo4 steel frame with aluminum subframe designed for lightweight agility and durability. Suspension includes WP XACT 48 mm upside-down front forks providing Approx. 310 mm travel and a WP XACT rear monoshock with linkage delivering Approx. 300 mm travel for precise track control. Braking is handled by a 260 mm front disc brake and 220 mm rear disc brake for consistent stopping performance. The motorcycle rides on 21-inch front and 19-inch rear spoked wheels with motocross tires 80/100 front and 100/90 rear. Additional specifications include seat height 950 mm, wheelbase Approx. 1485 mm, ground clearance Approx. 375 mm, dry weight Approx. 87.5 kg, bore 54 mm, stroke 54.5 mm, and fuel tank capacity Approx. 7.5 L.