These are the known mechanical and performance specifications for your 2009 Gilera GP 800 Centenario.
Basic Specs

Engine
Displacement839.30 ccm (51.21 cubic inches)
Type
DetailsV2, four-stroke
Max RPM
Compression10.5:1
Bore/Stroke88.0 x 69.0 mm (3.5 x 2.7 inches)
Valves/Cylinder4
FuelingInjection
IgnitionInductive discharge electronics and variable spark advance integrated into injection control unit, with electronic imobiliser, LED warning light and automatic lockout of injection pump if vehicle is tilted beyond road grip limits. Dual ignition
ExhaustClosed loop lambda probe system on exhaust and 3-way catalyser.
Lubrication
CoolingLiquid
Performance
Horespower65.50 HP (47.8 kW)
Torque76.40 Nm (7.8 kgf-m or 56.4 ft.lbs)
Top Speed
Fuel Economy & Polution
Fuel Consumption
Fuel Capacity18.50 litres (4.89 gallons)
Emissions
Chassis
Frame TypeDouble-cradle framework of high-tensile steel tubing. Carbon fibre parts.
Rake
Trail
Front SuspensionHydraulic telescopic fork with Ø 41 aluminium stanchions,
Front Travel122 mm (4.8 inches)
Rear SuspensionOhlins aluminium alloy rear swing-arm, with laterally-mounted, horizontally-positioned hydraulic monoshock, with adjustable preload, 7-position spring,
Rear Travel133 mm (5.2 inches)
Seat
Seat Height780 mm (30.7 inches) If adjustable, lowest setting.
Alt. Seat Height
Total Height
Total Length2,237 mm (88.1 inches)
Total Width
Ground Clearance
Wheelbase1,593 mm (62.7 inches)
Dry Weight243.0 kg (535.7 pounds)
Wet Weight260.0 kg (573.2 pounds)
Wheels & Brakes
Front Tire/Tyre120/70-16
Rear Tire/Tyre160/60-15
Front BrakesDouble disc. Bremo
Front Brake Diameter300 mm (11.8 inches)
Rear BrakesDouble disc. Bremo
Rear Brake Diameter280 mm (11.0 inches)
Wheels
Comments
Limited edition model for Gilera´s 100th birthday.