Quick Analysis
KTM 50 SX
9.5 pts
Unweighted: 4 advantages
EnginePerformanceDimensionsBrakesTyresOther
KTM 450 SX-F
24.5 pts
Unweighted: 14 advantages
EnginePerformanceDimensionsBrakesTyresOther
| Specification | ||
|---|---|---|
Engine Specifications |
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| Cooling System | — | Liquid cooled |
| Displacement | 49.9 cc | 449.9 cc |
| Engine Type | 1-cylinder, 2-stroke engine | 1-cylinder, 4-stroke engine |
| Power | 5.3 bhp @ 11500 rpm | — |
| Torque | 5.2 Nm @ 7500 rpm | — |
Performance & Efficiency |
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| Fuel Tank Capacity | 2.3 L | 7.2 L |
| Mileage | 30 kmpl | 15.33 kmpl |
Dimensions & Weight |
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| Kerb Weight | 41 kg | 107 kg |
| Seat Height | 653 mm | 958 mm |
Brakes & Suspension |
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| ABS | — | Dual Channel ABS |
| Front Brake | Disc 160 mm | Disc 260 mm |
| Front Suspension | XACT 35 WP Upside-Down fork, Ø 35 mm | WP XACT-USD (AER), Ø 48 mm |
| Rear Brake | Disc 160 mm | Disc 220 mm |
| Rear Suspension | XACT WP mono shock | WP XACT Monoshock with linkage |
Tyres & Wheels |
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| Front Tyre | 60/100 - 12 | 80/100 - 21 |
| Rear Tyre | 2.75 - 10 | 110/90 - 19 |
| Tyre Type | Tubed | Tubeless |
| Wheel Type | Spoke | Alloy |
Other Specifications |
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| Color Options | Electronic Orange | Orange |
| 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. | Very Tall Seat: At ~958 mm, it’s difficult to handle for shorter riders, especially off-road. Small Fuel Tank: The 7.2-liter tank limits how far you can ride — built more for racing than touring. Harsh Power Delivery: The high-revving engine is race-tuned, which may be too aggressive for casual use or beginners. Vibrations: The single-cylinder engine can vibrate strongly, especially at higher RPMs. High Maintenance Cost: Premium motocross parts and servicing (suspension, clutch, engine) can be expensive. Limited Street Usability: Not ideal for daily commuting due to track-focused ergonomics and setup. Reliability Trade-offs: Some riders report issues under hard race-type use, like stripped screws or wear on high-stress parts. |
| 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 450 SX-F is a high-performance motocross machine built to compete at the highest level; it’s engineered for speed, agility, and race track domination rather than casual cruising. At its core lies a 449.9 cc four-stroke, single-cylinder, liquid-cooled engine, tuned to generate strong and immediate power with a broad rev range. This powertrain is designed to make explosive bursts out of corners, offer consistent throttle response, and deliver a raw racing feeling. The engine’s lightweight construction contributes significantly to the bike’s competitive edge, keeping the overall weight low and enabling sharp acceleration. KTM has optimized the 450 SX-F’s handling through a sophisticated chassis and suspension setup. The bike features WP XACT 48 mm inverted front forks and a matching WP XACT rear shock which combine to offer generous travel (around 310 mm front and 300 mm rear), excellent damping, and great control during jumps or uneven terrain. This suspension system provides riders with a stable and predictable ride, whether they’re launching off a tabletop or navigating whoops on a technical track. The frame itself, likely a high-grade steel trellis design, balances rigidity and flexibility to help maintain stability under heavy loads while allowing for sharp and responsive feedback when pushed aggressively. Electronics on the 450 SX-F reflect its competitive nature. It comes equipped with launch control, enabling better starts during drag-style races. Additionally, the bike offers selectable engine mappings and traction control, giving riders the flexibility to choose different levels of assistance based on track conditions. These systems help control wheel spin, optimize torque delivery, and enhance safety at high RPMs. The inclusion of a quickshifter goes a long way in making aggressive riding smoother, while the engine maps help tailor performance for dry, dusty tracks or slippery surfaces. Though a serious racewheel, KTM hasn’t skimped on user convenience: the 450 SX-F includes an electric starter, so riders don’t need to rely on kick-starting, a welcome feature for modern motocross users. The ergonomics are built for competition: a high seat height (~958 mm) and tall, wide handlebars give the rider a commanding posture, facilitating balance and control over big jumps and landings. Despite being built for off-road prowess, the rider’s triangle provides a decent balance—standing up or sitting down remains natural and feels intentional, rather than an afterthought. The bike’s weight is impressively kept in check, making it lighter than many of its peers. This low weight improves not only maneuverability but also helps reduce rider fatigue during extended sessions on the track. At the same time, the drivetrain is engineered with a 5-speed gearbox, making gear changes efficient and suited to the demands of motocross. The clutch is performance-oriented, ensuring durability and precise engagement under racing stress. Fuel capacity is modest (around 7.2 liters), which is typical for a motocross bike but restricts the 450 SX-F to race or track use rather than long-distance adventures. Maintenance is regular and can be demanding: high-revving competition engines demand careful attention to oil changes, suspension settings, and component wear. Still, many motocross riders consider this a fair trade-off given the bike’s competitive performance. In summary, the KTM 450 SX-F is a race-bred motocross machine that delivers raw power, high agility, and top-tier handling. It’s not designed for comfort cruising or commuting—it’s built for serious track work and competitive environments. For riders who live for the thrill of racing, who demand the sharpest throttle response, and who don’t shy away from the maintenance demands of four-stroke competition bikes, the 450 SX-F is a standout performer. |
| 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 450 SX-F? A: The bike is powered by a 449.9 cc, single-cylinder, 4-stroke liquid-cooled engine. Q: What is the power and torque output? A: According to specs, the 450 SX-F produces about 62.96 PS and approximately 74 Nm of torque. Q: What kind of transmission does it have? A: It uses a 5-speed gearbox. Q: What is the fuel tank capacity? A: The fuel tank capacity is around 7.2 litres. Q: What is the seat height and ground clearance? A: The seat height is 958 mm, and ground clearance is very high at 343 mm. Q: What suspension setup is used on the 450 SX-F? A: It comes with WP XACT 48 mm USD front forks and a WP XACT monoshock with linkage. Q: What brakes does it have? A: The 450 SX-F is equipped with a 260 mm front disc and a 220 mm rear disc. Q: What electronic / rider-aid features does it include? A: It comes with launch control, quickshifter, selectable engine maps + traction control (TC), and a connectivity unit for off-road use. Q: What is the weight of the 450 SX-F? A: The kerb weight is approximately 107 kg for the standard model. Q: Does this bike have an electric starter? A: Yes, it has a self-starter (electric), so you don’t need to kick-start it. Q: What kind of fuel should I use? A: The manufacturer recommends high-octane / race-grade fuel for optimal performance. However, some users mention that standard premium pump gas (91 RON) works “just fine” on a stock setup. Q: How reliable is the 450 SX-F? A: While KTM 450s are high-performance machines, many owners report good longevity with regular maintenance. Some have raised concerns about top-end rebuilds, but others say healthy use with regular oil changes can bring 180+ hours before any major work. |
| Price Variants | | 475000 | | 1025100 |
| 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. | Very High Performance: The 449.9 cc single-cylinder engine delivers strong, race-ready power for motocross. Light and Agile: With its low weight (around 107 kg) and compact frame, it’s extremely maneuverable on tracks. Top-Tier Suspension: Equipped with WP XACT 48 mm USD forks and a high-travel rear shock, making it very capable over jumps and rough terrain. Modern Electronics: Includes launch control, selectable engine maps, quickshifter, and traction control for improved control. Electric Start: Convenient and practical — no need for kick-starting. Strong Chassis: The trellis frame offers a good mix of stiffness and flexibility, ideal for aggressive riding. Serviceability: Easy access to key components like the air filter and suspension for maintenance. |
| Transmission | Manual | 5 Speed Manual |
