KTM 85 SX The Gateway to Motocross Greatness Bike

The KTM 85 SX brings big-bike performance to young riders, blending race-winning technology, agility, and power in a compact motocross machine designed for champions.

The KTM 85 SX stands as one of the most respected names in youth motocross, bridging the gap between mini motocross bikes and full-sized machines. Designed for aspiring racers ready to make the leap into competitive off-road riding, this machine encapsulates KTM’s racing DNA in a compact, lightweight, and extremely capable package. For many young riders, the 85 SX is more than just a bike—it’s a stepping stone to professional racing careers and a thrilling introduction to the world of high-performance motocross.

Design and Build: A Scaled-Down Race Weapon

At first glance, the KTM 85 SX looks every bit like its bigger siblings from the SX lineup. Its aggressive styling, sharp lines, and race-focused ergonomics immediately set the tone. The slim bodywork, flat seat profile, and narrow waistline allow riders to move freely and shift their body weight effortlessly during intense riding sessions.

KTM engineers have intentionally designed the bike to replicate the feel and balance of their full-size motocross machines. The lightweight chromium-molybdenum steel frame offers an optimal mix of rigidity and flex, ensuring stability at high speeds while maintaining agility in corners. The orange frame and graphics are distinctly KTM—bold, youthful, and unmistakably race-ready.

The ergonomics are tailored to growing riders, ensuring a perfect balance between control and comfort. Whether the rider is standing on the pegs during jumps or leaning into tight turns, the 85 SX provides an intuitive connection between rider and machine.

Engine: Small in Size, Big in Power

Powering the KTM 85 SX is a high-performance 84.9cc two-stroke, single-cylinder engine that’s anything but ordinary. This compact powerhouse delivers exhilarating acceleration and impressive top-end performance, all while maintaining predictable power delivery for developing riders.

KTM’s two-stroke technology is world-renowned for its responsiveness and simplicity. The engine features a power valve system, which automatically adjusts exhaust port timing to provide smooth torque at lower RPMs and explosive power at higher revs. This means riders get the best of both worlds—tractable performance for technical sections and fierce acceleration for straights and jumps.

A six-speed gearbox with precise shifting complements the engine’s power characteristics, while a hydraulically operated clutch ensures consistent performance and light lever action. This combination allows young riders to focus on their technique and racecraft without struggling with mechanical limitations.

Despite its small displacement, the KTM 85 SX feels every bit like a professional motocross bike—fast, responsive, and packed with adrenaline.

Chassis and Suspension: Built for Competition KTM 85 SX

A race machine needs race-grade components, and the KTM 85 SX delivers exactly that. The bike features WP XACT suspension at both ends, setting the benchmark for performance in this segment. Up front, the WP XACT 43mm USD air fork provides exceptional damping control, allowing riders to adjust air pressure for personalized settings. This ensures the suspension can be fine-tuned for varying rider weights and track conditions without the need for complicated tools.

At the rear, the WP XACT PDS mono-shock is directly connected to the swingarm, providing progressive damping and outstanding stability over jumps and rough terrain. Together, the suspension setup provides an incredibly balanced and forgiving ride, instilling confidence in riders as they push their limits.

The lightweight frame, complemented by a high-strength aluminum subframe, keeps the overall weight impressively low—around 67 kg (dry). This translates to agile handling and quicker acceleration out of corners, especially important for young riders honing their racing skills.

Braking and Wheels: Precision and Control

KTM equips the KTM 85 SX with high-performance wave disc brakes, offering strong and consistent stopping power. The front brake features a 240mm disc paired with a robust caliper, while the rear uses a 210mm disc, ensuring responsive braking across all conditions. These brakes are designed to withstand the heat and stress of competitive racing, giving riders the confidence to brake late into corners and maintain speed through tight sections.

The 85 SX rolls on lightweight black anodized aluminum rims with MAXXIS tires, engineered for superior grip on motocross tracks. The 17-inch front and 14-inch rear wheel setup is standard on the small-wheel version, while the big-wheel variant comes with a 19-inch front and 16-inch rear configuration—perfect for taller or more advanced riders.

This combination of precise braking and durable tires ensures total control, whether it’s navigating technical obstacles or charging down the straightaways.

Ergonomics and Rider Experience KTM 85 SX

The KTM 85 SX doesn’t just perform—it also fits perfectly. The adjustable handlebar position, narrow seat, and grippy footpegs create a riding triangle that allows natural body movement. Every control, from the clutch to the throttle, has been designed with younger riders in mind.

Despite being a youth bike, the 85 SX feels remarkably premium. The clutch lever is hydraulically actuated, ensuring light feel and consistent engagement. The throttle action is smooth and predictable, giving riders fine control over power delivery. These subtle yet significant touches enhance the overall riding experience and help riders develop their skills with precision.

For parents and trainers, KTM’s build quality means fewer mechanical issues and more track time. The easy maintenance of the two-stroke engine and accessible components make servicing quick and straightforward, allowing young racers to focus on what truly matters—improving their lap times.

Performance on Track: Built to Win KTM 85 SX

Take the KTM 85 SX to a motocross track, and it immediately feels at home. The combination of its lightweight construction, powerful engine, and precision suspension makes it incredibly nimble and responsive. Whether it’s taking tight berms, clearing tabletops, or navigating whoops, the 85 SX reacts instantly to rider input.

Its balance and handling inspire confidence even in riders who are transitioning from smaller 65cc bikes. The linear power delivery ensures the engine remains manageable, yet thrilling enough to challenge and excite. The chassis’ feedback allows riders to learn advanced control techniques—such as throttle modulation, body positioning, and braking precision—that will serve them well as they progress into larger displacement classes.

It’s this blend of performance and learning potential that makes the KTM 85 SX a favorite among young champions and motocross schools worldwide.

Verdict: The Perfect Stepping Stone for Future Champions

The KTM 85 SX is more than just a motocross bike—it’s a training ground for the next generation of professional riders. It captures the essence of KTM’s “Ready to Race” philosophy in a compact, rider-friendly format that encourages skill development and competitive spirit.

Every detail, from its precision-engineered engine to its race-proven suspension, reflects KTM’s commitment to performance excellence. It’s lightweight, durable, and explosively fun to ride—everything a young racer could ask for.

For riders aged around 11 to 15 who dream of podium finishes, the 85 SX is not just a start—it’s a statement. It’s where the journey toward motocross greatness truly begins.

Last Updated On 27 October 2025.