Engineered by Polini for the minibike, sport motorcycle segment, the 2007 Polini 911 GP4 features a 39.7 cc (2.4 cu in) air-cooled single cylinder, two-stroke configuration. In factory specification, peak output is rated at 4.2 HP (3.1 kW), transferring power to the rear wheel through a 6-speed gearbox and chain final drive. Internal engine geometry specifies a bore and stroke of 36.0 x 39.0 mm (1.4 x 1.5 inches) with a 14.0:1 compression ratio.
On the scales, the 911 GP4 measures 22 kg (49 lbs) dry. Rider ergonomics and chassis geometry center around a 425 mm (16.7 in) seat height — giving shorter riders and urban commuters confident flat-foot reach at traffic stops.
Standover Height
425 mm (16.7 in)
Engine
Displacement39.7 ccm (2.42 cubic inches)
Engine TypeSingle cylinder, two-stroke
Engine DetailsSingle cylinder, two-stroke
Power4.2 HP (3.1 kW))
Compression14.0:1
Bore x Stroke36.0 x 39.0 mm (1.4 x 1.5 inches)
Valves/Cylinder0
Fuel SystemCarburettor. SHA 14.14
Fuel ControlReed valve / power valve
IgnitionCDI
LubricationSeparate lubrication with automatic oil pump
CoolingAir
Transmission
Gearbox6-speed
Final DriveChain (final drive)
ClutchDry with centrifuge counter weigths
DrivelineChain final drive
Chain Size420
Chassis
Frame TypeLatticed tubular frame
Wheels & Brakes
Front Tyre90/65-R6.5
Rear Tyre110/50-R6.5
Front BrakesSingle disc
Front Brake Ø148 mm (5.8 inches)
Rear BrakesSingle disc
Rear Brake Ø130 mm (5.1 inches)
Dimensions & Weight
Dry Weight22.0 kg (48.5 pounds)
Power/Weight0.1909 HP/kg
Seat Height425 mm (16.7 inches) If adjustable, lowest setting.
Overall Length960 mm (37.8 inches)
Overall Width240 mm (9.4 inches)
Oil Capacity1.30 litres 2T reservoir / 0.80 L gearbox
Service & Fluids
Engine Oil2-stroke synthetic motorcycle oil (API TC / JASO FC/FD)
Brake FluidDOT 4
Spark PlugsNGK BR9ES / BR9EG
Battery12V 4Ah (YTX4L-BS)
Other
StarterKick
Color OptionsBlue/white
Electrical12V 4Ah (YTX4L-BS)
Notes
They are intended solely for competiton-sports usage. Use on public highways is prohibited.
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.
Transmission
Transmission and final drive affect maintenance, smoothness and everyday usability.
