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MotoLibrary Score
33/100Commuter
Power
9 HP
Torque
9 Nm
Engine
125 ccm
Technical Overview
2021 Um Flash 125 Technical Analysis & Specification Breakdown
Positioned in Um's scooter motorcycle lineup, the 2021 Um Flash 125 pairs a 125 cc (7.6 cu in) air-cooled single cylinder, four-stroke architecture with road-focused gearing. In factory specification, peak output is rated at 8.8 HP (6.5 kW) at 7,700 rpm while maximum torque reaches 9 Nm (6.6 lb-ft) at 6,000 rpm, transferring power to the rear wheel through a automatic gearbox and chain final drive. With a specific output of 70.4 HP per liter and a 1,700 rpm working window between peak torque (6,000 rpm) and peak power (7,700 rpm), the engine character is indicating a tractable, stress-free state of tune focused on everyday usability and broad torque delivery.
Rider ergonomics and chassis geometry center around a 770 mm (30.3 in) seat height — offering a neutral standover height that accommodates most average-inseam riders without sacrificing cornering clearance, combined with a 1,250 mm (49.2 in) wheelbase engineered for quick, flickable steering geometry.
Specific Output
70.4 HP/L
Power Band Window
6,000–7,700 rpm
Standover Height
770 mm (30.3 in)
Engine
Displacement125.0 ccm (7.63 cubic inches)
Engine TypeSingle cylinder, four-stroke
Power8.8 HP (6.5 kW)) @ 7700 RPM
Torque9.0 Nm (0.9 kgf-m or 6.6 ft.lbs) @ 6000 RPM
Compression9.0:1
Bore x Stroke54.0 x 54.0 mm (2.1 x 2.1 inches)
IgnitionC.D.I
CoolingAir
Transmission
GearboxAutomatic
Final DriveChain (final drive)
Chassis
Front SuspensionTelescopic fork
Rear SuspensionMonoshock
Wheelbase1250 mm (49.2 inches)
Wheels & Brakes
Front Tyre70/90-17
Rear Tyre80/90-17
Front BrakesSingle disc
Rear BrakesExpanding brake (drum brake)
Dimensions & Weight
Seat Height770 mm (30.3 inches) If adjustable, lowest setting.
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.
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.
