New 2022 KTM 150 SX Mx Motorcycle

The KTM 150 SX is a lively package that is quite literally in a class of its own. With enough firepower to take on the 250 cc 4-Strokes, a lightweight chassis, and a compact engine producing class-leading torque and power, the KTM 150 SX provides an unparalleled motocross experience unlike anything before it.

Engine & Exhaust

• Engine: The pure exhilaration that this bike’s engine delivers warranted continued production. As it shares many of its key components with the class-leading 125, the cylinder, cylinder head and piston unit can now also be fitted on a 125 cc engine base, converting it to a 150 SX without having to replace the crankshaft. Compact and powerful, this innovative 2-stroke engine is a lightweight powerhouse that just makes perfect sense.
• Cylinder: At the heart of the 150 cc engine is a 58 mm bore cylinder. It features an innovative power valve unit with a sophisticated mechanism designed for the lateral support exhaust ports. The exhaust port layout enhances engine performance, while the precise machining of the upper contour of the exhaust port ensures accurate port timing. The two component cylinder head works in complete harmony with the cylinder to deliver outstanding performance across the entire rev range.
• Crankcases And Engine Covers: The lightweight engine cases are manufactured using a high pressure die-cast production process, keeping wall thickness to a minimum while retaining strength and durability. The design allows for a high crankshaft position which is located near to the center of gravity, resulting in optimal mass centralization and easier rideability. The engine body is extremely compact, which contributes significantly to the low engine weight. Additionally for 2020, the kickstart intermediate gear has been reworked for improved reliability.
• Transmission: The KTM 150 SX is fitted with a robust 6-speed transmission. The gear ratios, which featured improvements and reinforcements, were carried over from the predecessor. The gearbox features a new drive shaft which uses a screw for pinion fixation and diaphragm spring instead of a circlip, ensuring secure pinion fixation. Another highlight of the 125 SX transmission is the “no-dirt” gear shifter. Similar to the footpeg design, it prevents the build-up of dirt and ensures the next gear is always available, no matter what the conditions.
• Carburetor: The KTM 150 SX is fitted with a MIKUNI TMX 38 mm flat slide carburetor featuring settings that were adapted to suit the new airbox developed in 2019. For 2020, reworked reeds for intake reed block provide further improvements in function, sealing and reliability, ensuring the whole system is always providing smooth, controllable power throughout the rev range.