Quick Analysis
KTM 50 SX
6.5 pts
Unweighted: 3 advantages
EnginePerformanceDimensionsBrakesTyresFeaturesOther
KTM 390 DUKE
26.0 pts
Unweighted: 20 advantages
EnginePerformanceDimensionsBrakesTyresFeaturesOther
| Specification | ||
|---|---|---|
Engine Specifications |
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| Cooling System | — | Liquid cooling with radiator |
| Displacement | 49.9 cc | 398.63 cc |
| Engine Type | 1-cylinder, 2-stroke engine | Single Cylinder, Liquid Cooled, DOHC, FI Engine |
| Power | 5.3 bhp @ 11500 rpm | 46 PS @ 8500 rpm |
| Torque | 5.2 Nm @ 7500 rpm | 39 Nm @ 6500 rpm |
Performance & Efficiency |
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| Fuel Tank Capacity | 2.3 L | 15 L |
| Mileage | 30 kmpl | 30 kmpl |
Dimensions & Weight |
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| Kerb Weight | 41 kg | 168.3 kg |
| Seat Height | 653 mm | 800 mm |
Brakes & Suspension |
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| ABS | — | Dual-channel ABS with SUPERMOTO mode |
| Front Brake | Disc 160 mm | 320 mm Disc with Radially mounted calliper |
| Front Suspension | XACT 35 WP Upside-Down fork, Ø 35 mm | 5-click Compression & Rebound adjustable, Open Cartridge, WP APEX USD forks, 43mm diameter |
| Rear Brake | Disc 160 mm | 240 mm Disc with Floating calliper |
| Rear Suspension | XACT WP mono shock | Adjustable WP APEX Monoshock, 5-step Rebound damping, 10-step preload adjustable |
Tyres & Wheels |
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| Front Tyre | 60/100 - 12 | 110/70 - ZR17 |
| Rear Tyre | 2.75 - 10 | 150/60 - ZR17 |
| Tyre Type | Tubed | Tubeless |
| Wheel Type | Spoke | Alloy |
Features & Technology |
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| Headlight | — | Full Split LED Headlamp |
Other Specifications |
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| Battery | — | 12 V, 8 AH MF battery |
| Bike Image 1 | — | https://motoautiv.com/wp-content/uploads/2025/11/KTM-390-Duke-Electric-orange.webp |
| Bike Image 2 | — | https://motoautiv.com/wp-content/uploads/2025/11/KTM390DukeBlack_Booking.webp |
| Cluster | — | 5" TFT dash display |
| Color Options | Electronic Orange | GUN METAL GREY ELECTRONIC ORANGE ATLANTIC BLUE |
| Cons | High Maintenance: As a 2-stroke engine, it requires frequent servicing and tuning. Small Fuel Tank: Limited capacity means more frequent refills. Kick-Start Only: No electric start, which can be tricky for very young riders. Limited Power for Older Kids: The 50cc engine may not be enough as the rider grows or becomes more skilled. Sensitive to Tuning: Owners report issues like fouling spark plugs or needing to frequently re-jet the carb: “Used to run great … then started fowling plugs … Moved to a 95 main jet … About 15 kph slower …” Parts Cost & Availability: As a race‑oriented bike, some parts can be expensive or harder to source for older models. | Firm (harsh) ride: The suspension can feel stiff over potholes or uneven surfaces, which may be tiring for long rides. Limited wind protection: Being a naked bike, you feel a lot of wind at highway speeds, making long-distance touring less comfortable. Engine heat: In slow or stop-go traffic, the radiator fan can dump hot air toward the rider’s legs, which many find uncomfortable. Seat comfort: The stock seat can feel firm and less comfortable for long rides; also, pillion comfort is limited. Vibration: Some riders report noticeable vibrations in certain RPM ranges, especially between ~4,500–6,000 rpm. Reliability concerns: There are occasional reports of reliability issues or quality control, especially in older models. |
| Detailed Overview | The KTM 50 SX is a purpose-built mini motocross bike, tailored primarily for very young and beginner racers who want to get a genuine motocross experience without jumping straight to bigger bikes. It’s more than just a “toy” — KTM has packed serious race-bike DNA into this 50cc model, making it a standout choice for youth motocross training and competitive racing. At the heart of the 50 SX is a 49.9 cc single-cylinder 2-stroke engine, which delivers a punchy yet manageable power output. According to KTM’s specs, this engine is paired with a centrifugal automatic clutch, meaning there’s no manual clutch lever to worry about — the clutch engages automatically, which is ideal for young riders still building coordination and confidence. The engine uses a Seletra 2p D36 system for fuel delivery (on some models), which helps in precise tuning and reliable performance. KTM has thoughtfully designed the chassis for both strength and agility. The frame is made from chromoly steel, which keeps it light but sturdy. The overall design ensures that the bike is highly maneuverable, making it easier for young riders to learn balance and control on a real race-ready structure. The 50 SX isn’t just about motor and frame — it comes with serious suspension too: a WP XACT 35 mm upside-down fork at the front and a WP mono‑shock at the rear.The front suspension travel is around 200 mm and the rear is close to 190 mm, giving enough give for track bumps and jumps. In terms of ergonomics, the seat height is just 653 mm, making it very accessible for younger riders. Ground clearance is around 233 mm, giving the bike enough space to handle uneven terrain without scraping too much.The fuel tank capacity is modest — 2.3 liters — but that’s more than enough for short motocross sessions that young riders typically do. For braking, KTM hasn’t compromised: the 50 SX is equipped with disc brakes both front and rear, each 160 mm in size. This provides good stopping power and control, which is very important for safety and learning advanced braking techniques. On the wheels front, the bike uses spoke wheels, keeping things light and rugged for off-road racing. Despite its small size, the 50 SX is very race-focused. The frame has been redesigned to mimic the flex and rigidity characteristics of full-size MX bikes. The new frame also comes with frame protectors, which help reduce damage in case of falls — a common occurrence when young riders are learning. The handlebars are lightweight aluminum, with a bend that suits smaller riders, and the footpegs are designed to give a solid grip even when things get muddy or rough. KTM also includes power-reduction kits in its parts catalog for the 50 SX. These kits let parents or coaches limit the power output while the rider is still learning, which is a smart way to scale the bike’s performance to the rider’s ability — and once they’re better, the full power can be unlocked. When it comes to reliability, the 50 SX has a liquid cooling system for better thermal management. The engine’s central crankshaft design helps in keeping the mass well-balanced, which contributes to smoother handling. As for maintenance, like all 2-stroke motorcycles, it does need regular care — but KTM has made key parts (like the clutch) durable, using a reinforced clutch basket for longevity. Overall, the KTM 50 SX is a very well-engineered youth motocross bike that brings real race performance to younger riders. It balances power, weight, and control in a way that helps beginners grow into serious racers. Whether for track training, competitive racing, or just building early riding skills, it’s absolutely one of the top choices in the mini-moto world. | The **KTM 390 Duke** has long been celebrated as a high-performance yet lightweight streetfighter, offering a compelling mix of power, agility, and modern technology that makes it a favorite for both urban commuting and spirited weekend rides. The latest (Gen-3) 390 Duke takes this formula further, built on a newly designed trellis frame with a die-cast aluminium sub-frame that improves rigidity and handling. Under the hood, the 2024 model is powered by a liquid-cooled, single-cylinder “LC4c” engine now displacing **399 cc**, which bumps up the performance to roughly **46 PS of power and 39 Nm of torque** in the Indian spec. One of the most striking traits of the 390 Duke is its lightness: the new model continues to boast sporty handling thanks to its steel trellis frame and a compact, aggressive footprint. The WP APEX 43 mm upside-down front fork and a preload-adjustable WP APEX mono-shock at the rear provide a finely tuned suspension setup that balances comfort on city roads with precision in the corners. Braking is handled by a 320 mm front disc with a radial calliper and a 230 mm rear disc, supported by Bosch cornering ABS, giving reliable and controllable stopping performance. On the feature front, the 2024 Duke 390 is truly packed. It includes ride modes (Street, Rain, Track), launch control, SuperMoto ABS, a quickshifter+, and a slipper clutch. The ride-by-wire throttle ensures smooth power delivery and precise control, especially when transitioning between modes. Its 5-inch TFT display supports smartphone connectivity (via Bluetooth) for turn-by-turn navigation, calls, and media, making it a very usable bike for daily commuting. Ergonomically, the 390 Duke offers a sporty but accessible riding position. The seat height is around **800 mm** in the Indian variant, with an optional 820 mm seat available, making it relatively manageable for a variety of rider heights. The fuel tank is reasonably sized (KTM lists about 13.4 litres), which balances enough capacity for daily use without compromising on agility. In terms of usability, the 390 Duke shines in city traffic thanks to its light weight, responsive throttle, and nimble chassis. At the same time, its torque and power allow for satisfying highway stretches and sporty ride-outs. However, as some users note, the high-revving single cylinder can vibrate noticeably at lower RPMs, and the engine tends to heat up in slow, stop-go traffic — a common character point for small high-performance singles. On long highway rides, wind protection is minimal due to the naked nature, and though the electronics are rich, some may feel the bike’s seat and fuel range are not optimized for extended touring. Reliability-wise, many long-term owners report good durability when properly maintained. One rider, after 29,000 km, said he never faced major breakdowns and appreciated the bike’s consistent performance. That said, some others have expressed concern about vibration and the need for regular maintenance given the sporty nature of the engine. Overall, the **KTM 390 Duke** is a brilliant all-rounder in the 300–400 cc naked category. It offers serious performance, modern electronics, and a lightweight chassis, but it doesn’t compromise on practicality. For someone looking for a fun, aggressive bike that can do daily duties and weekend thrills, the 390 Duke remains one of the most compelling choices in its class. |
| Expert Review | MotoAutiv Team | MotoAutiv Team |
| FAQ (Manual Override) | Q: What is the engine capacity of the KTM 50 SX? A: It has a 49.9 cc 2-stroke engine. Q: What kind of transmission does it use? A: The KTM 50 SX has a single-speed automatic transmission. Q: How is the KTM 50 SX started? A: It uses a kick-start. Q: Does it have a clutch? A: Yes — a centrifugal (adjustable) clutch, so the rider doesn’t have to use a manual clutch lever. Q: What is the fuel tank capacity? A: The fuel tank capacity is 2.3 litres. Q: What is the seat height? A: The seat height is 653 mm. Q: What is the weight of the bike? A: The dry (or “without fuel”) weight is about 43.5 kg for recent models. Q: What kind of suspension does the KTM 50 SX use? A: It comes with WP XACT suspension — a 35 mm upside-down fork in the front and a WP mono-shock at the rear. Q: What brakes does it have? A: It has disc brakes both at the front and rear, each 160 mm. Q: What power does the KTM 50 SX produce? A: The KTM 50 SX produces around 5.3–5.4 PS at ~11,500 rpm. Q: Is the KTM 50 SX road legal? A: No — it's designed for off-road / motocross use, not for street-legal riding. Q: What kind of clutch does it have for young riders? A: It uses a centrifugal clutch, which automatically engages at high RPM — good for beginners or young riders who don’t manually operate a clutch. Q: What is the ground clearance? A: The ground clearance is 233 mm. Q: Is there a guarantee or warranty for KTM 50 SX? A: According to specs, it has a 2-year standard warranty. Q: What is the typical maintenance challenge or issue to watch for? A: Some owners report carburetor tuning issues | Q: What engine does the KTM 390 Duke have? A: It uses a single-cylinder, liquid-cooled, DOHC engine. Q: What is the displacement, power & torque of the 390 Duke? A: The displacement is about 398.6 cc. In the newer versions, it produces around 46 PS at 8,500 rpm and 39 Nm of torque at 6,500 rpm. Q: What is the seat height and weight of the 390 Duke? A: The seat height is 800 mm (or optionally 820 mm) depending on the version. The kerb weight is about 168.3 kg per KTM’s specification. Q: What is the fuel tank capacity and what is the mileage like? A: The fuel tank capacity is 15 litres in many versions. According to some sources, real-world fuel efficiency is around 25–30 km/l, depending on riding style. Q: What brakes and suspension does it use? A: It comes with WP APEX 43 mm upside-down front forks and a WP APEX monoshock at the rear. For brakes, there is a 320 mm front disc and a 240 mm rear disc, with a radially mounted caliper up front. Q: What is the ground clearance of the 390 Duke? A: The ground clearance is around 183 mm according to KTM India specifications. Q: What is the seat configuration and ergonomics like? A: It has a two-part seat design, with a slightly aggressive but comfortable rider position thanks to its upright handlebars. There’s also a “Supermoto mode” which lets you limit ABS intervention to the front brake — great for sliding control. Q: Does the 390 Duke come with smartphone connectivity? A: Yes — some variants support KTM MY RIDE via the 5-inch TFT dash, allowing for calls, music, and navigation integration. |
| Price Variants | | 475000 | Standard | 297443 |
| Pros | Very Lightweight: Makes it easy for young riders to handle and build confidence. Automatic Transmission: The centrifugal clutch and automatic gearbox simplify riding for beginners. Adjustable Suspension: High-quality WP fork and shock can be tuned to rider weight and track conditions. Racing‑Oriented Build: Frame and components are derived from KTM’s full-size SX range, giving a race-ready feel. Power-Reduction Kits Available: Helps beginners by limiting power until they’re ready for more. Good Cooling: Liquid cooling ensures the engine stays healthy even under hard off‑road use. Tool-Free Adjustability: Seat height, suspension, and other parts can be adjusted without special tools. | Excellent performance for its class: The 390 Duke’s single-cylinder engine delivers punchy acceleration and strong mid-range performance. Lightweight & nimble: With a relatively low kerb/wet weight, its chassis is very agile, making it easy to flick through corners and manoeuvre in traffic. Advanced electronics suite: Comes equipped with ride modes, traction control (MTC), cornering ABS, supermoto ABS, quickshifter, and a modern TFT display. Adjustable suspension: The front and rear suspension are adjustable (WP APEX), allowing riders to tune the setup depending on road conditions or riding style. Sharp styling & design: Features such as an exposed steel trellis frame, LED headlight, and aggressive design make it visually striking. Good build quality: Reviews note improved fit and finish on newer models, giving a premium feel. Decent fuel efficiency: Compared to its performance, it offers reasonable fuel efficiency for sporty riding. |
| Transmission | Manual | 6 Speed Manual |
