2021 Sinnis Jet II Technical Analysis & Specification Breakdown
At the heart of the 2021 Sinnis Jet II scooter motorcycle, Sinnis relies on a 50 cc (3.1 cu in) air-cooled single cylinder, four-stroke powerplant. In factory specification, peak output is rated at 3.9 HP (2.8 kW) at 7,500 rpm, transferring power to the rear wheel through a automatic gearbox and belt final drive. With a specific output of 78 HP per liter, the engine character is indicating a tractable, stress-free state of tune focused on everyday usability and broad torque delivery.
On the scales, the Jet II measures 135 kg (298 lbs) dry. Rider ergonomics and chassis geometry center around a 710 mm (28 in) seat height — giving shorter riders and urban commuters confident flat-foot reach at traffic stops, combined with a 1,370 mm (53.9 in) wheelbase engineered for quick, flickable steering geometry.
Within MotoLibrary's Sinnis archive, this model family spans 2 indexed model years from 2020 to 2021, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.
Specific Output
78 HP/L
Standover Height
710 mm (28 in)
Engine
Displacement50.0 ccm (3.05 cubic inches)
Engine TypeSingle cylinder, four-stroke
Power3.9 HP (2.8 kW)) @ 7500 RPM
Fuel SystemCarburettor. Delphi
CoolingAir
Transmission
GearboxAutomatic
Final DriveBelt (final drive)
Chassis
Front SuspensionTelescopic Forks
Rear SuspensionCoil Spring
Wheelbase1370 mm (53.9 inches)
Wheels & Brakes
Front Tyre3.50-10
Rear Tyre3.50-10
Front BrakesSingle disc. Hydraulic.
Rear BrakesExpanding brake (drum brake)
Dimensions & Weight
Dry Weight135.0 kg (297.6 pounds)
Power/Weight0.0288 HP/kg
Seat Height710 mm (28.0 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.
Seat Height
Check the seat height against your inseam and riding posture before choosing a motorcycle.
Weight
Compare weight carefully because it affects low-speed handling, parking and confidence.
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.
