The journey starts here. The first prime platform in the KTM Sportminicycle range will satisfy any youngster's thirst for fun, speed, adventure and that unquenchable desire to learn. The KTM 50 SX is built around an advanced steel frame, housing a powerful engine, an updated WP XACT AER fork, a WP XACT monoshock, and a new, advanced hydraulic Formula brake system. Reliability, durability and READY TO RACE aesthetics and spirit means it is the only choice for small kids and the big ones too!
Different adjustability options were built into the KTM 50 SX construction using scientific statistical data and young racers' input data. Finding the right fit for your little ripper is easy thanks to height-adjustable suspension, handlebar position, subframe, and bodywork, taking the seat height from a low setting of 24.9 in (634 mm) to a taller setting of 26.8 in (682 mm).
Ignition
A digital ignition from Hidria finds its way onto the KTM 65 SX, with improved processing power and ignition curve, making for a cleaner burn and smoother power delivery. The throttle assembly benefits from a stabilization cap that extends the lifetime of the cable by reducing the risk of kinking and damage.
Carburetor
A proven Dell'Orto type PHBG 19 BS carburetor takes a prime position in producing the goods in the KTM 50 SX, working perfectly in harmony with the engine, exhaust, and air intake design.
For absolute beginners, the KTM POWERPARTS catalog offers a choice of two power-reduction kits. The first allows for a entry-level, moderate and controllable power reduction to 4hp, with the second permitting more intermediate power kit unleashing 8hp for mid-level riding levels.
Performance
The KTM 50 SX features a modern and compact engine using the latest 2-stroke technology. Using a 3-shaft design, the crankshaft is positioned near the center of gravity, which not only benefits mass centralization but also creates the ideal intake angle into the reed valve for top-level performance. For 2026, the transmission shafts are new developments with wider dimensions and several components have been reinforced to enhance durability.
Clutch
The KTM 50 SX is fitted with a centrifugal clutch reducing the complexity for younger riders, and helping to boost riding confidence. The multi-disc clutch delivers a precise and predictable power delivery across the RPM range. It can be set to suit rider preferences or track conditions without using any special tools. Also, a reinforced clutch basket provides extra durability, wear, and consistent performance. The clutch itself receives a boost in quality with a high-strength pre-coat and increased tightening torque for reliable fastening of the whole assembly.
Spark Plug
There's no more worrying about breaking the plug, thanks to the KTM 50 SX featuring a spark plug from BRISK with a longer thread. Also, thanks to this innovation, the part number is printed on the spark plugs for easy reading.
The airbox features a conventional suction sleeve made from a hard-wearing polyamide instead of rubber and a Twin Air filter mounting system that features snap locks for easy and intuitive mounting. The Twin Air filter is also placed under the seat and is easily accessible without any tools by simply removing the seat. It also features improved dirt intrusion resistance, with no more dirt falling into the intake tract when changing the filter.
Ergonomics
Mimicking the full-size KTM SX range, the KTM 50 SX features the same advancements found in the larger KTM SXs. Slimmer, sleeker, and better suited to standing on the pegs, the side panels now work much better with young riders' boots, allowing a proper squeezing of the bike when standing up. The front number plate incorporates plastic flaps to protect the lower triple clamps from roost. Speaking of triple clamps, the model spectrum now has an improved fixing mechanism which hikes the lifespan of the steering head bearings thanks to the extra block from dirt and water. The wrench size is also smaller and more practical. The tank spoiler features a bicomponent technology featuring the KTM-specific texture on the upper part. Side number plates are kept as close to the frame as possible, with the general seat line sitting slightly flatter.
Handlebars & Grips
Hold on tight! The high-quality, tapered, black handlebar is made of lightweight aluminum alloy and ensures top stability, vibration damping, and control. It has been designed specifically with 65cc riders in mind, featuring a bend and profile for a more READY TO RACE body position. An ODI grip is used on the left side, while a vulcanized ODI grip is mounted on the right-side throttle assembly, with a crash pad on the handlebar protecting the rider from rough contact.
Frame
The KTM 50 SX boasts a high-strength chromium molybdenum steel frame design with forged connecting parts integrated into the frame. This together with carefully calculated parameters of longitudinal flex and torsional rigidity, allow tailormade stiffness and an unprecedented quality of the Mini frame. The frame layout features a typical MX design without any cross tube behind the steering head. Like our full-size models, the rear shock mount is separated from the main upper frame tube. The frame also comes with frame protectors as standard.
Rolling off the race rig and into the pit lane, the KTM 50 SX uses lightweight, black anodized, aluminum rims just like the full-size KTM SX range. These provide the highest levels of strength and reliability, while MAXXIS MX-ST tires deliver outstanding performance on any terrain, along with exceptional straight-line stability.
Footpegs
A "no-dirt" footrests offer a bigger surface area for improved grip while standing on the pegs, and are less susceptible to hooking up in deep ruts, take-offs when scrubbing, or track barriers.
Suspension
Featuring the latest in suspension technology, the KTM 50 SX has an updated state-of-the-art, lightweight 35 mm USD WP XACT AER fork. With 205 mm of wheel travel, the air unit in the left fork leg can also be adjusted easily using an air pump for rider preference, weight, or track conditions. The upgrade means better damping and control and is a step forward for the suspension performance. At the rear, fully-adjustable WP XACT monoshock boasts a mounting point on the frame making it more compact, providing the perfect balance and damping characteristics to match the fork.
Brakes
Featuring the same level of technology offered on the full-size KTM SX range, the 2025 KTM 50 SX is fitted with hydraulic brake calipers and state-of-the-art front and rear waved brake discs. This system ensures advanced braking feel and unmatched stopping performance in all conditions, specifically on wet or muddy tracks, with improved durability and brake pad longevity.
The exhaust system features the same manufacturing process as the full-size 2-stroke KTM SX range, with high overall quality and performance. This has resulted in massive progressions in thermodynamics. Moreover, improved sealing of the silencer end cap and a rubber between the header pipe and silencer add another level of quality to the exhaust system. The silencer comes with a black anodized finish and a signature 'Braaaaap!'. The modifications include a new flange gasket for better durability and the exhaust valve ventilation has been redesigned. It is more 'bulletproof' thanks to more efficient and locally sourced manufacturing at KTM HQ.
Radiator
The KTM 50 SX has state-of-the-art Pankl radiators inspired by the full-size KTM SX range and features the same basic design with all the hardcore cooling properties. The KTM 50 SX uses one large radiator with more capacity instead of two smaller separate ones. This concept allows for better integration of the radiator into the frame and the tank spoilers to channel air through the cooling fins efficiently. For 2026, a new threaded radiator cap allows easier and faster opening with reduced force.
Hour Meter
Keep track of engine hours easily, with an hour meter mounted at the same position behind the front number plate - as on the full-size KTM SX models. This makes for easier reading and has a lower risk of dirt and water fowling up the display.
Adjustablity
Ignition
Carburetor
Power-Reduction Kits
Performance 
Clutch
Spark Plug
Airbox and Filter
Ergonomics
Handlebars & Grips
Frame
Wheels & Tires
Footpegs 
Suspension
Brakes
Exhaust
Radiator
Hour Meter
KTM-technical-specifications (9).pdf
