Quick Analysis
KTM 50 SX
13.5 pts
Unweighted: 6 advantages
EnginePerformanceDimensionsBrakesTyresFeaturesOther
KTM 390 ADVENTURE X
16.5 pts
Unweighted: 13 advantages
EnginePerformanceDimensionsBrakesTyresFeaturesOther
| Specification | ||
|---|---|---|
Engine Specifications |
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| Displacement | 49.9 cc | 398.63cc |
| Engine Type | 1-cylinder, 2-stroke engine | — |
| Power | 5.3 bhp @ 11500 rpm | 46 @ 8500 |
| Torque | 5.2 Nm @ 7500 rpm | 39 @ 6500 |
Performance & Efficiency |
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| Fuel Tank Capacity | 2.3 L | 14.5 |
| Mileage | 30 kmpl | 30 kmpl |
Dimensions & Weight |
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| Kerb Weight | 41 kg | 181 |
| Seat Height | 653 mm | 825 |
Brakes & Suspension |
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| ABS | — | Switchable ABS |
| Front Brake | Disc 160 mm | 320 |
| Front Suspension | XACT 35 WP Upside-Down fork, Ø 35 mm | WP APEX USD forks, 43 mm diameter, 200mm travel |
| Rear Brake | Disc 160 mm | 240 |
| Rear Suspension | XACT WP mono shock | WP APEX Monoshock, 205mm wheel travel Adjustable for Preload (10 steps) |
Tyres & Wheels |
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| Front Tyre | 60/100 - 12 | 100/90 x 19 |
| Rear Tyre | 2.75 - 10 | 130/80x17 |
| Tyre Type | Tubed | Tubeless |
| Wheel Type | Spoke | Alloy |
Features & Technology |
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| Headlight | — | LED headlamp |
Other Specifications |
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| Bike Image 1 | — | https://motoautiv.com/wp-content/uploads/2025/11/KTM-390-Adventure-X_White.webp |
| Color Options | Electronic Orange | Electronic Orange Ceramic White |
| 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. | Tall Seat Height: At 825 mm, the seat may be uncomfortable or difficult to reach for shorter riders, especially off-road. Lack of Cornering ABS: Unlike the standard 390 Adventure, the X variant skips cornering ABS, which reduces safety margin when leaning hard. Limited Traction Control: Fewer electronic aids compared to higher-spec ADVs — could be less forgiving on unpredictable terrain. Vibrations at High RPMs: The single-cylinder engine can produce noticeable vibrations when pushed hard, affecting comfort. Moderate Wind Protection: The windscreen and fairing design might not deflect wind strongly enough at high speeds. Suspension Can Feel Harsh on Pavement: While great off-road, the long-travel suspension may feel firm or bouncy on uneven city roads. Maintenance Cost: Premium suspension components and tech might lead to higher service costs compared to simpler commuter bikes. Limited Pillion Comfort: The seat design and limited rear padding may not provide much comfort for a passenger over long distances. |
| 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 Adventure X is a scaled-down, lightweight adventure motorcycle designed to give riders a taste of serious off-road experience without stepping into the realm of big-bore ADV bikes. Built to be agile yet capable, the 390 Adventure X combines rugged design, modern technology, and a peppy engine to deliver a balanced and versatile package. The motorcycle is powered by a 398 cc single-cylinder, liquid-cooled engine that makes about 46 PS and 39 Nm of torque, which gives it the right punch for both highway rides and trail days. One of the most appealing aspects of the Adventure X is its chassis and suspension setup. With WP APEX 43 mm USD front forks and a capable rear monoshock, the motorcycle offers good travel and suspension compliance. Its ground clearance of approximately 228 mm makes it suitable for mild to moderate off-road terrain, while its relatively light kerb weight improves maneuverability. Riders can confidently tackle gravel roads, broken trails or even slower forest paths, thanks to the suspension and lightweight design, making it a true entry-level adventure bike with real trail capability. KTM has equipped this motorcycle with modern electronics to back up its rugged design. A 5-inch TFT display serves as the cockpit, giving the rider access to useful ride data like gear position, speed, trip information, fuel, and more. The bike also supports Quickshifter+ for clutchless upshifts and downshifts in favorable conditions, enhancing the sporty feel. While the 390 Adventure X omits some high-end electronics like cornering ABS or full stability control, it includes switchable off-road ABS to allow controlled rear-wheel sliding for better off-trail control. Ergonomically, the Adventure X leans into KTM’s adventure-riding DNA with a tall seat, wide handlebars, and an upright riding position. This setup allows riders to stand comfortably on the footpegs—a critical feature when riding on uneven terrains. Despite its adventure-focused build, the 14.5-litre fuel tank gives it enough range for weekend touring or mixed terrain trips, particularly when coupled with the engine’s efficiency. In terms of design, the 390 Adventure X is rugged and purposeful. It features adventure-ready styling with skeletal fairing, broad fuel tank covers, an adjustable windscreen, and robust graphics that align with its off-road intentions. The slim bodywork and adventure-inspired elements give it an aesthetic that is as functional as it is stylish. While the 390 Adventure X is capable in a variety of conditions, it’s not without trade-offs. The tall seat height can be a hurdle for shorter riders, and the firm suspension may feel a bit harsh on smooth city roads. The lack of advanced rider aids like cornering ABS may deter some who ride aggressively on twisty roads. Vibration from the single-cylinder engine at high revs is also a possibility, especially when pushed hard. Despite these compromises, the KTM 390 Adventure X remains a compelling choice for riders who want real adventure capability in a manageable, lightweight frame. It’s ideal for new or intermediate dual-sport enthusiasts who want a rugged bike that excels off-road but doesn’t feel overkill on the pavement. With a strong balance of performance, technology, and capability, the 390 Adventure X reinforces KTM’s position in the adventure motorcycle segment by offering substance without overwhelming complexity. |
| 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 is the engine specification of the KTM 390 Adventure X? A: The 390 Adventure X is powered by a single-cylinder, liquid-cooled engine. According to KTM India, its displacement is 398.63 cc, producing 46 PS @ 8,500 rpm and 39 Nm torque @ 6,500 rpm. Q: What type of transmission does this bike use? A: It uses a 6-speed gearbox, according to KTM’s technical specs. Q: What is the fuel tank capacity and the expected range? A: The Adventure X comes with a 14.5 litre fuel tank. This gives it decent range for touring, especially when combined with its efficient engine. Q: What is the seat height and ground clearance? A: The seat height is 825 mm, according to several official sources. The ground clearance is 228 mm, which helps its off-road credentials. Q: What suspension setup does the 390 Adventure X use? A: It features WP APEX 43 mm USD front forks with 200 mm of travel, and a WP APEX monoshock at the rear. Q: What brakes and ABS features are on this bike? A: The bike uses a 320 mm front disc and 240 mm rear disc, per KTM’s spec sheet. It also offers switchable ABS, including an Off-Road mode, but does not have cornering ABS on this X variant. Q: What electronic rider aids are offered? A: The Adventure X includes Ride-by-Wire throttle, a Quickshifter+, and switchable off-road ABS. Unlike the standard 390 Adventure, it doesn't include features like cornering ABS or full traction control (MTC). Q: What does the instrument panel look like? A: It comes with a 5-inch TFT display that provides essential ride information and adapts to ambient light. Q: Is the Adventure X good for off-road riding? A: Yes — with its 19″ front / 17″ rear wheel setup, high ground clearance, and off-road ABS, it’s designed to tackle dirt trails and gravel while remaining very capable on-road. Q: What is the kerb / wet weight of the bike? A: The kerb (fully fueled) weight is around 176 kg, per KTM’s UK technical spec sheet. Q: What is the rated fuel efficiency / mileage? A: According to sources like BikeWale, the mileage is claimed to be around 30 km/l for the 390 Adventure X. Some real-world owners report 21–25 km/l, depending on conditions. Q: Are there some known issues or drawbacks reported by owners? A: Yes — several riders mention vibrations at higher RPMs, particularly in the footpegs and handlebar. Also, some users believe KTM has compromised on certain parts quality (e.g., the side stand assembly) to cut costs. |
| Price Variants | | 475000 | | 326178 |
| 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. | Lightweight & Nimble: Being a small-displacement ADV, it’s easier to manage than larger dual-sport bikes, making it ideal for both urban and trail use. Good Power for Class: Its ~398 cc single-cylinder engine provides enough punch for highway cruising and off-road sections without being too intimidating. Long-Travel Suspension: Equipped with WP APEX USD forks and a capable rear monoshock, it offers very good travel for handling rough terrain. High Ground Clearance: With around 228 mm of ground clearance, the 390 Adventure X is well-suited for mild to moderate off-road trails. Off-Road ABS Mode: Switchable ABS allows the rear wheel to slide slightly in off-road mode, which provides more control on loose surfaces. Modern Tech Features: Features like Quickshifter+, ride-by-wire throttle, and a 5-inch TFT display add a premium, tech-savvy feel. Good Fuel Range: With a 14.5 L fuel tank and decent efficiency, it offers a respectable touring range for a mid-sized ADV. Durable Build: Trellis frame and quality components contribute to its rugged build, making it reliable for adventure rides. |
| Transmission | Manual | 6 Speed Manual |
