2018 KTM 85 SX 17/14

The 11 to 15-year-old riders of the junior class are no longer beginners. These are future champions fighting for victory, no matter if it is the for a National Championship or a local qualifier. In this scene, the new and improved KTM 85 SX is considered a winner’s bike. With the most powerful engine in the field and a super lightweight, stable chassis, it does not need to shy away from a full size bike.

ENGINE

Cutting-edge 2-stroke technology, combined with a precise 6-speed transmission and hydraulic clutch are the foundation of the KTM 85 SX’s superiority in all junior racing competition. The new KTM 85 SX engine uses the latest technology to deliver unrivaled performance in the competitive 85cc class. With an unchanged bore and stroke, the engine is 1.5 pounds lighter and delivers improved power and rideability along the complete rev range. Key to the engine is a new power valve which allows the power delivery to be tailored simply and more effectively than before.

CYLINDER

The new cylinder has an unchanged bore and stroke (47/48.95mm) with new ports to improve performance and response. Additionally, it is designed around an all new power valve system. This system controls both the exhaust valve and the sub exhaust port for significantly improved power, torque and controllability. As a result, the KTM 85 SX receives a significant increase in mid-range performance reducing the need to use the clutch in loamy or sandy conditions. An adjuster screw allows the opening timing of the power valve to be adjusted to suit rider preference and track conditions and by changing between different power valve springs (available in the KTM PowerParts catalog).

CRANKSHAFT

The new crankshaft is now lighter with optimized balancing to reduce vibration and oscillating mass. Even after removing this weight, the rotational inertia of the crankshaft has increased by 0.5kg improving torque and rideability.

EXHAUST SYSTEM

The new exhaust system is perfectly suited to the engine’s power characteristics and contributes to the outstanding performance and rideability. The pipe is made in a 3-dimentional stamping process by WP Performance Systems. Once the components are shaped they are robot welded to ensure the highest level of quality and durability. The new silencer is 50mm shorter, improving mass centralization.

CLUTCH

The hydraulic clutch mechanism by Formula ensures an easy clutch action and well-defined modulation on the KTM 85 SX. Replacing the previous coil spring design, the KTM 85 SX features a new diaphragm spring clutch. The new design is 0.8 pounds lighter, more compact and also benefits from added durability.

CRANKSHAFT

The all-new crankshaft is now lighter with optimized balancing to reduce vibration and oscillating mass. Even after removing this weight, the rotational inertia of the crankshaft has increased by 1 pound, improving torque and rideability. Thanks to its perfectly sized lightweight connecting rod, the crankshaft is distinguished by minimum vibrations and maximum durability.