KTM 65 SX vs KX 85
The youth motocross scene has never been more competitive, and choosing the right bike can make all the difference in a young rider’s development. Two machines stand at the forefront of this exciting segment: the Austrian-engineered KTM 65 SX and the Japanese powerhouse Kawasaki KX 85. While these bikes cater to different age groups and skill levels, they represent the pinnacle of youth motocross technology and performance. As we accelerate through 2025, understanding the strengths and characteristics of each machine becomes crucial for parents and young riders aiming for podium finishes and skill development.
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The Youth Motocross Landscape
Youth motocross represents more than just a stepping stone to professional racing—it’s where young riders develop skills, confidence, and a lifelong passion for dirt bike riding. The choice between a 65cc and 85cc machine depends on the rider’s age, size, experience level, and competitive aspirations. Both KTM and Kawasaki have spent decades refining their youth motocross offerings, incorporating technology from their professional racing programs.
KTM’s dominance in motocross racing translates directly into their youth models. The 65 SX has become the benchmark in the 65cc class, winning countless championships and developing future champions. The bike represents KTM’s “Ready to Race” philosophy scaled down for younger riders without compromising on performance or quality.
Kawasaki’s KX 85 continues the legacy of the legendary KX series, offering reliable performance and proven technology. The bike serves as the final step in youth motocross before transitioning to full-size machines, making it crucial for developing advanced riding skills and race craft.
Engine Performance: Small Displacement, Big Power
The KTM 65 SX features a 64.9cc liquid-cooled, single-cylinder two-stroke engine that produces impressive power for its displacement. The engine delivers explosive acceleration and a broad powerband that’s manageable yet thrilling for young riders. Weighing just 62 kg, the bike offers an excellent power-to-weight ratio that allows young riders to experience genuine motocross performance.
The engine features a six-speed gearbox with precise shifting characteristics, allowing riders to select the perfect gear for any situation. The transmission is robust enough to handle aggressive riding while remaining smooth enough for developing riders to master gear selection techniques.
The Kawasaki KX 85 steps up with an 84cc liquid-cooled, single-cylinder two-stroke engine that delivers significantly more power. This larger displacement translates to higher top speeds and stronger acceleration, making it suitable for older, more experienced riders transitioning toward full-size bikes. At 74.6 kg, the KX 85 is heavier than the 65 SX, which is expected given its larger engine and overall dimensions.
The KX 85’s six-speed gearbox features tight ratios optimized for motocross racing. The transmission allows riders to keep the engine in its powerband throughout the track, teaching valuable shifting skills that transfer directly to larger displacement machines.
Chassis and Suspension: Race-Ready Foundations
Both motorcycles feature premium chassis designs that prioritize lightweight construction and optimal rigidity. The frames are engineered to provide excellent handling characteristics while remaining durable enough to withstand the rigors of motocross racing and practice sessions.
The KTM 65 SX boasts WP XACT suspension components—the same technology used on KTM’s professional racing machines. The upside-down fork provides 215mm of travel, while the rear shock offers excellent damping characteristics. The suspension is fully adjustable, allowing parents and mechanics to dial in settings based on track conditions and rider weight.
The compact dimensions of the 65 SX make it perfect for riders aged 8-12, depending on their size and experience. The ergonomics are carefully designed to allow young riders to move freely on the bike, teaching proper riding techniques from an early age.
The Kawasaki KX 85 features larger dimensions suitable for riders aged 10-15. The bike comes in two wheel size configurations: standard 19-inch front/16-inch rear, or the “big wheel” version with 17-inch rear. This versatility allows the bike to grow with the rider, extending its usability across multiple seasons.
The KX 85’s suspension offers generous travel with quality damping characteristics. While not featuring the premium components of the KTM, the suspension works exceptionally well for its intended purpose and is fully adjustable to accommodate different rider weights and skill levels.
Build Quality and Reliability: Investment Considerations
KTM’s reputation for producing championship-winning machines comes with premium pricing and maintenance requirements. The 65 SX features top-shelf components throughout, from the engine to the suspension and brakes. This translates to exceptional performance but requires diligent maintenance to keep the bike performing at its peak.
Regular maintenance on the KTM includes frequent oil changes, air filter servicing, and periodic top-end rebuilds typical of high-performance two-stroke engines. Parts availability is generally good through KTM dealers, though costs can be higher than Japanese alternatives.
The Kawasaki KX 85 is renowned for its reliability and durability. Japanese engineering focuses on producing machines that perform consistently over extended periods with regular maintenance. The KX 85 typically requires less frequent major service intervals, making it more economical for families on a budget.
Kawasaki’s extensive dealer network and parts availability make ownership straightforward. Replacement parts tend to be more affordable than KTM equivalents, and the bike’s proven design means mechanics are familiar with service requirements.
Handling and Performance: Track Domination
The KTM 65 SX is widely regarded as the best-handling bike in its class. The lightweight construction combined with premium suspension creates a machine that changes direction effortlessly. Young riders can develop proper cornering techniques and aggressive riding styles without being overwhelmed by excessive weight or power.
The bike’s ergonomics encourage movement and active riding. The narrow profile allows riders to grip the bike firmly with their knees, teaching fundamental riding techniques that become crucial as they progress to larger machines.
The Kawasaki KX 85 offers stability and planted handling characteristics that build confidence at higher speeds. The bike feels more substantial than smaller displacement machines, helping riders transition to the weight and feel of full-size motocross bikes. The handling is predictable and confidence-inspiring, allowing riders to focus on improving their skills rather than fighting the bike.
Braking Performance: Safety First
Both motorcycles feature hydraulic disc brakes front and rear, providing strong, progressive stopping power. The brake systems are appropriately sized for the bikes’ performance capabilities, ensuring young riders can stop effectively without experiencing overwhelming brake force.
The KTM 65 SX features high-quality brake components that offer excellent feel and modulation. The system provides consistent performance throughout long practice sessions or race motos.
The Kawasaki KX 85’s braking system is robust and reliable, offering strong stopping power with good feel. The larger brake rotors complement the bike’s increased weight and power, ensuring safe deceleration from higher speeds.
Price and Value: Making the Investment
Pricing represents a significant consideration when choosing youth motocross bikes. The KTM 65 SX commands premium pricing due to its championship-winning pedigree and top-tier components. While the initial investment is substantial, many families find the performance advantage and resale value justify the cost.
The Kawasaki KX 85 offers excellent value, typically priced lower than the KTM while still delivering quality performance. The bike’s reliability and lower maintenance costs make it an economical choice for families with multiple young riders or tighter budgets.
Both bikes hold their value well in the used market, as demand for quality youth motocross bikes remains strong. Proper maintenance and care significantly impact resale values for both models.
Which Bike Should You Choose?
Choose the KTM 65 SX if your young rider is in the 65cc class (typically ages 7-11) and shows serious racing potential. The bike is perfect for families committed to competitive motocross who want the best possible equipment. The 65 SX rewards aggressive riding and helps develop advanced skills that translate directly to larger bikes. It’s the choice of champions and provides the performance advantage needed at the highest levels of youth racing.
Opt for the Kawasaki KX 85 if your rider is ready for 85cc power (typically ages 10-15) and needs a reliable, proven machine that balances performance with practicality. The KX 85 excels as a training tool for riders preparing to transition to full-size bikes. It’s ideal for families wanting quality performance without premium pricing, and its reliability makes it perfect for riders who practice frequently.
Training and Development: Building Future Champions
Both motorcycles serve as exceptional platforms for skill development. The KTM 65 SX teaches young riders about aggressive riding, bike control, and the importance of maintaining race pace. Its championship-winning DNA instills confidence and competitive spirit.
The Kawasaki KX 85 prepares riders for the physical and mental demands of adult motocross racing. The increased power and weight help develop strength and stamina while teaching advanced techniques necessary for competitive success on larger machines.
The Final Verdict
The KTM 65 SX versus Kawasaki KX 85 comparison isn’t truly apples-to-apples due to their different displacement classes. However, both represent the pinnacle of their respective categories. The 65 SX dominates the 65cc class with unmatched performance and championship pedigree, while the KX 85 offers proven reliability and excellent value in the 85cc segment.
Your choice should reflect your rider’s age, size, experience level, and competitive goals. For younger riders in the 65cc class seeking maximum performance, the KTM 65 SX stands unrivaled. For riders ready to step up to 85cc power and preparing for full-size bikes, the Kawasaki KX 85 provides reliable performance at excellent value.
Both machines have launched countless professional careers and created lifelong motocross enthusiasts. Whether you choose Austrian engineering excellence or Japanese reliability, your young rider will experience the thrill of genuine motocross performance. The dirt awaits, and either of these machines will provide the perfect platform for developing skills, chasing podiums, and creating memories that last a lifetime.
