Built around Sym's scooter motorcycle platform, the 2025 Sym ADX 125 pairs a 125 cc (7.6 cu in) liquid-cooled single cylinder, four-stroke architecture with road-focused gearing. In factory specification, peak output is rated at 12.1 HP (8.8 kW) at 7,500 rpm while maximum torque reaches 11.5 Nm (8.5 lb-ft) at 7,000 rpm, transferring power to the rear wheel through a automatic gearbox and belt final drive. With a specific output of 96.8 HP per liter and a 500 rpm working window between peak torque (7,000 rpm) and peak power (7,500 rpm), the engine character is reflecting a performance-oriented street tune that balances strong mid-range pull with an energetic top-end rush.
Rider ergonomics and chassis geometry center around a 750 mm (29.5 in) seat height — giving shorter riders and urban commuters confident flat-foot reach at traffic stops, combined with a 1,390 mm (54.7 in) wheelbase engineered for quick, flickable steering geometry. The 15-liter (4 US gal) fuel tank supports practical everyday commuting and weekend road stints.
Within MotoLibrary's Sym archive, this model family spans 3 indexed model years from 2023 to 2025, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.
Specific Output
96.8 HP/L
Power Band Window
7,000–7,500 rpm
Standover Height
750 mm (29.5 in)
Engine
Displacement125.0 ccm (7.63 cubic inches)
Engine TypeSingle cylinder, four-stroke
Power12.1 HP (8.8 kW)) @ 7500 RPM
Torque11.5 Nm (1.2 kgf-m or 8.5 ft.lbs) @ 7000 RPM
Bore x Stroke53.0 x 56.5 mm (2.1 x 2.2 inches)
Fuel SystemInjection. EFI
Fuel ControlOverhead Cams (OHC)
CoolingLiquid
Transmission
GearboxAutomatic
Final DriveBelt (final drive)
DrivelineCVT
Performance
Emission DetailsEuro 5+
Chassis
Front SuspensionTelescope fork
Rear SuspensionSingle-sided Mono-shock
Wheelbase1390 mm (54.7 inches)
Wheels & Brakes
Front Tyre120/70-13
Rear Tyre130/70-13
Front BrakesSingle disc. ABS.
Front Brake Ø260 mm (10.2 inches)
Rear BrakesSingle disc. ABS.
Rear Brake Ø230 mm (9.1 inches)
Dimensions & Weight
Seat Height750 mm (29.5 inches) If adjustable, lowest setting.
Overall Height1225 mm (48.2 inches)
Overall Length1980 mm (78.0 inches)
Overall Width780 mm (30.7 inches)
Fuel Capacity15.00 litres (3.96 US gallons)
Other
StarterElectric
Color OptionsBlack, grey, white, green, Blue
InstrumentsLCD instrument panel
LightLED head light, LED position light, LED tail light, and LED turn indicators.
Notes
The SYM brand is owned by Sanyang Motor in Taiwan.
Use this page to compare this motorcycle by its real specifications, not only by model name. Focus on the details that affect fit, comfort, handling, range and ownership.
Power
Compare engine output with similar motorcycles if acceleration, highway use or two-up riding matters.
Torque
Torque is useful for judging real-world pull, especially for touring, commuting and loaded riding.
Seat Height
Check the seat height against your inseam and riding posture before choosing a motorcycle.
Fuel Capacity
Fuel capacity helps estimate touring range and how often you may need to stop.
Brakes
Brake setup is worth comparing if you ride in traffic, mountains or with a passenger.
Suspension
Suspension details can matter for comfort, road feel and long-distance riding.
Transmission
Transmission and final drive affect maintenance, smoothness and everyday usability.
