US$ 4999. MSRP depends on country, taxes, accessories, etc.
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MotoLibrary Score
36/100Commuter
Power/Weight
0.07 hp/kg
Torque
25 Nm
Engine
387 ccm
Technical Overview
2012 BamX BX400-U4 Sierra Technical Analysis & Specification Breakdown
Engineered by BamX for the atv motorcycle segment, the 2012 BamX BX400-U4 Sierra features a 387 cc (23.6 cu in) oil & air-cooled single cylinder, four-stroke configuration. In factory specification, peak output is rated at 19 HP (13.9 kW) while maximum torque reaches 25 Nm (18.4 lb-ft) at 5,500 rpm, transferring power to the rear wheel through a automatic gearbox and shaft drive (cardan) final drive. With a specific output of 49.1 HP per liter, the engine character is prioritizing low-RPM tractability, mechanical longevity and relaxed throttle response over peak redline numbers.
On the scales, the BX400-U4 Sierra measures 266.3 kg (587 lbs) dry, translating to a power-to-weight ratio of 0.07 HP/kg (14.02 kg per horsepower). Rider ergonomics and chassis geometry center around a 864 mm (34 in) seat height — reflecting a long-travel chassis stance that favors ground clearance and off-pavement control, combined with a 1,245 mm (49 in) wheelbase engineered for quick, flickable steering geometry. The 13.5-liter (3.6 US gal) fuel tank supports practical everyday commuting and weekend road stints.
Specific Output
49.1 HP/L
Power-to-Weight
0.07 HP/kg (14.02 kg/HP)
Standover Height
864 mm (34 in)
Engine
Displacement387.0 ccm (23.61 cubic inches)
Engine TypeSingle cylinder, four-stroke
Engine DetailsSingle cylinder, four-stroke
Power19.0 HP (13.9 kW))
Torque25.0 Nm (2.5 kgf-m or 18.4 ft.lbs) @ 5500 RPM
Compression9.5:1
Bore x Stroke83.0 x 71.6 mm (3.3 x 2.8 inches)
Fuel SystemCarburettor
IgnitionCDI
LubricationPressure/Splash
CoolingOil & air
Transmission
GearboxAutomatic
Final DriveShaft drive (cardan) (final drive)
DrivelineCVT Fully Automatic w/Reverse
Chassis
Front SuspensionDouble A-Arm
Rear SuspensionSwing Arm
Wheelbase1245 mm (49.0 inches)
Ground Clearance254 mm (10.0 inches)
Wheels & Brakes
Front Tyre25/8-12
Rear Tyre25/10-12
Front BrakesDouble disc
Rear BrakesSingle disc
Dimensions & Weight
Dry Weight266.3 kg (587.0 pounds)
Power/Weight0.0714 HP/kg
Seat Height864 mm (34.0 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.
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.
Weight
Compare weight carefully because it affects low-speed handling, parking and confidence.
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.
