These are the known mechanical and performance specifications for your 2011 Yamaha BWs 12inch.
Basic Specs

Engine
Displacement49.20 ccm (3.00 cubic inches)
Type
DetailsSingle cylinder, two-stroke
Max RPM
Compression7.2:1
Bore/Stroke40.0 x 39.2 mm (1.6 x 1.5 inches)
Valves/Cylinder
Fueling
IgnitionCDI
Exhaust
LubricationSeparate lubrication
CoolingAir
Performance
Horespower3.22 HP (2.4 kW)
Torque3.60 Nm (0.4 kgf-m or 2.7 ft.lbs)
Top Speed
Fuel Economy & Polution
Fuel Consumption
Fuel Capacity5.30 litres (1.40 gallons)
Emissions
Chassis
Frame TypeSteel
Rake
Trail
Front SuspensionTelescopic fork
Front Travel70 mm (2.8 inches)
Rear SuspensionUnit swing
Rear Travel70 mm (2.8 inches)
Seat
Seat Height768 mm (30.2 inches) If adjustable, lowest setting.
Alt. Seat Height
Total Height
Total Length1,685 mm (66.3 inches)
Total Width
Ground Clearance124 mm (4.9 inches)
Wheelbase1,172 mm (46.1 inches)
Dry Weight82.0 kg (180.8 pounds)
Wet Weight
Wheels & Brakes
Front Tire/Tyre120/70-12
Rear Tire/Tyre130/70-12
Front BrakesSingle disc
Front Brake Diameter180 mm (7.1 inches)
Rear BrakesExpanding brake (drum brake)
Rear Brake Diameter110 mm (4.3 inches)
Wheels
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