KTM 125 Duke [2021-2022] Review: The Pint-Sized Predator
Introduction
The KTM 125 Duke has always been the rebel of the entry-level motorcycle segment, and the 2021-2022 iteration doubles down on this reputation. Designed for riders who refuse to compromise between style and substance, this bike packs the DNA of KTM’s larger naked machines into a 125cc package that’s legal for A1 license holders. Whether you’re threading through city traffic or carving backroads, the Duke delivers an experience that feels anything but "entry-level." Let’s dissect why this orange-hued pocket rocket continues to turn heads and thrill new riders.
Design & Ergonomics: Aggression Meets Accessibility
The 125 Duke’s design language screams "mature aggression." Its angular bodywork, split LED headlight, and exposed steel trellis frame (painted in KTM’s signature orange) give it a visual punch that outclasses most 125cc rivals. The black/orange color scheme isn’t just eye-catching—it’s a statement of intent.
At 830 mm (32.7 inches), the seat height is approachable for shorter riders, though the narrow profile of the bike makes it feel even lower. The rider triangle leans slightly sporty, with mid-set pegs and a flat handlebar that encourages an engaged posture. At 139 kg (306 lbs) dry, the Duke feels almost toy-like when pushing it off the stand, yet the chassis has a reassuring solidity.
Practical touches include a 13.4L (3.5-gallon) fuel tank with a sculpted knee indent and a minimalist tail section. The LCD dash is basic but legible, showing gear position, fuel economy, and ABS status. While taller riders might crave more legroom on longer rides, the Duke’s compact dimensions are perfect for urban commutes.
Performance: Small Displacement, Big Personality
Don’t let the 124.7cc displacement fool you—this single-cylinder mill is a gem. The liquid-cooled, DOHC engine with Bosch fuel injection produces 15 HP (11 kW) at 10,500 rpm and 12 Nm (8.9 lb-ft) of torque at 8,000 rpm. It’s Euro5-compliant, but KTM’s engineers have avoided strangling its character.
From idle, the engine feels eager. Throttle response is crisp, and the 6-speed gearbox (a rarity in this class) allows precise control over the powerband. First gear is short for city crawling, while sixth acts as an overdrive for relaxed highway cruising. Keep the revs above 7,000 rpm, and the Duke rewards with a surprisingly throaty exhaust note.
Fuel efficiency is stellar at 2.42 L/100 km (97 mpg), translating to a 300+ km (186-mile) range. That said, the Duke isn’t just a commuter. On twisty roads, the motor’s linear delivery encourages you to wring it out—a joy reinforced by the slick clutch and light shift action.
Handling & Dynamics: Precision Tool
The Duke’s chassis is its party piece. The steel trellis frame and 1357 mm (53.4-inch) wheelbase strike a perfect balance between agility and stability. Combine this with premium WP Apex suspension—43 mm USD forks up front and a preload-adjustable monoshock—and you’ve got a bike that dances through corners.
Lean angles are limited only by the 175 mm (6.9-inch) ground clearance and your courage. The 17-inch wheels shod with 110/70 (front) and 150/60 (rear) tires provide tenacious grip, while the Supermoto ABS lets you disable rear ABS for controlled slides (if you’re feeling adventurous).
Braking is another highlight. The ByBre 4-piston radial caliper biting a 300 mm front disc offers bite and feel that rivals bigger bikes. Even during hard stops, the dual-channel ABS intervenes smoothly, inspiring confidence in wet conditions.
Competition: How the Duke Stacks Up
The 125cc naked segment is fiercely contested. Here’s how the Duke battles its rivals:
- Yamaha MT-125: The MT matches the Duke’s 15 HP but uses a crossplane-inspired engine for a throatier sound. However, its conventional forks and heavier 140 kg (309 lbs) frame make it less flickable.
- Honda CB125R: Honda’s Neo-Sports Café stunner boasts premium Showa suspension and LED lights. Its engine is smoother at low RPMs but lacks the Duke’s top-end zest.
- Aprilia SX 125: More dirt-biased with longer suspension travel, the Aprilia appeals to dual-sport fans but feels less precise on pavement.
The Duke’s trump cards are its race-bred suspension, aggressive ergonomics, and that KTM "wild child" aura. It’s the choice for riders who prioritize handling over outright comfort.
Maintenance: Keeping the Beast Hungry
The 125 Duke isn’t high-maintenance, but it demands attention to stay sharp:
- Oil Changes: Use semi-synthetic 10W-40 or 15W-50 oil every 5,000 km (3,100 miles). The 1.5L capacity (with filter) makes DIY changes affordable.
- Valve Checks: KTM recommends inspecting valve clearances every 10,000 km (6,200 miles). Intake: 0.10–0.15 mm (0.004–0.006 in), exhaust: 0.15–0.20 mm (0.006–0.008 in).
- Chain Care: The 520 X-ring chain needs regular cleaning and lubrication. Adjust slack to 55–60 mm (2.2–2.4 in) for optimal drivetrain life.
- Coolant & Brakes: Replace coolant every 2 years and flush brake fluid (DOT 4/5.1) annually. The ByBre calipers benefit from periodic pad inspections.
For upgrades, MOTOPARTS.store offers everything from sintered brake pads to adjustable levers. Consider a tail tidy or slip-on exhaust to amplify the Duke’s attitude.
Conclusion: The Ultimate Gateway Drug
The 2021-2022 KTM 125 Duke isn’t just a starter bike—it’s a masterclass in how to make small-displacement motorcycling exhilarating. Its razor-sharp handling, premium components, and head-turning design create a package that’s impossible to ignore. While it won’t win drag races against larger bikes, it teaches you to ride with precision and flair.
For new riders, it’s a confidence-builder. For seasoned veterans, it’s a reminder of why lightweight bikes are so addictive. And for MOTOPARTS.store customers, it’s a blank canvas waiting for personalization. Slap on some bar-end mirrors, upgrade the tires, and this pocket-sized Duke will keep you grinning long after you’ve "outgrown" it.
Specifications sheet
| Engine | |
|---|---|
| Stroke: | Four-stroke |
| Max power: | 11 kW | 15.0 hp |
| Max torque: | 12 Nm |
| Fuel system: | Bosch electronic fuel injection |
| Max power @: | 10500 rpm |
| Displacement: | 125 ccm |
| Max torque @: | 8000 rpm |
| Bore x stroke: | 58.0 x 47.2 mm (2.3 x 1.9 in) |
| Configuration: | Single |
| Cooling system: | Liquid |
| Compression ratio: | 14.5:1 |
| Emission standard: | EURO5 |
| Lubrication system: | Wet sump |
| Number of cylinders: | 1 |
| Dimensions | |
|---|---|
| Wheelbase: | 1357 mm (53.4 in) |
| Dry weight: | 139 |
| Seat height: | 830 mm (32.7 in) |
| Ground clearance: | 175 mm (6.9 in) |
| Fuel tank capacity: | 13.4 L (3.5 US gal) |
| Drivetrain | |
|---|---|
| Chain type: | 520 X-ring |
| Final drive: | chain |
| Transmission: | 6-speed |
| Rear sprocket: | 45 |
| Front sprocket: | 14 |
| Primary drive ratio: | 22:72 |
| Electrical | |
|---|---|
| Battery: | 12V 8Ah maintenance-free |
| Starter: | Electric |
| Ignition system: | Fully electronic Kokusan ignition |
| Maintainance | |
|---|---|
| Engine oil: | 10W-40/15W-50 |
| Idle speed: | 1500 ± 50 rpm |
| Brake fluid: | DOT 4/5.1 |
| Spark plugs: | NGK CR8E |
| Coolant capacity: | 1.0 |
| Engine oil capacity: | 1.5 |
| Tire pressure (rear): | 2.0 bar (29 psi) solo / 2.2 bar (32 psi) with passenger |
| Tire pressure (front): | 2.0 bar (29 psi) |
| Engine oil change interval: | Every 5000km or 2 years |
| Valve clearance (intake, cold): | 0.10–0.15 mm |
| Final drive adjustment interval: | Every 1000 km (chain tension/lubrication) |
| Valve clearance (exhaust, cold): | 0.15–0.20 mm |
| Chassis and Suspension | |
|---|---|
| Frame: | Steel trellis frame, powder coated |
| Tire rear: | 150/60-17 |
| Tire front: | 110/70-17 |
| Rear brakes: | Single 230 mm disc, 1-piston floating caliper (Bosch 9.1MB ABS) |
| Front brakes: | Single 300 mm disc, 4-piston radial caliper (Bosch 9.1MB ABS) |
| Rear suspension: | WP APEX Monoshock (adjustable preload) |
| Front suspension: | 43 mm WP APEX USD fork |
| Rear wheel travel: | 150 mm (5.9 in) |
| Front wheel travel: | 142 mm (5.6 in) |
| Rake (steering head angle): | 65° |
