These are the known mechanical and performance specifications for your 2010 Derbi Senda Baja 125R.
Basic Specs

Engine
Displacement124.10 ccm (7.57 cubic inches)
Type
DetailsSingle cylinder, four-stroke
Max RPM
Compression9.2:1
Bore/Stroke56.5 x 49.5 mm (2.2 x 1.9 inches)
Valves/Cylinder2
FuelingCarburettor. 26 mm
IgnitionCDI
Exhaust
LubricationWet sump
CoolingAir
Fuel Economy & Polution
Fuel Consumption
Fuel Capacity8.00 litres (2.11 gallons)
Emissions
Chassis
Frame Type
Rake
Trail
Front Suspension41mm hydraulic fork.
Front Travel195 mm (7.7 inches)
Rear SuspensionMonoshock.
Rear Travel200 mm (7.9 inches)
Seat
Seat Height890 mm (35.0 inches) If adjustable, lowest setting.
Alt. Seat Height
Total Height
Total Length
Total Width
Ground Clearance
Wheelbase1,452 mm (57.2 inches)
Dry Weight118.0 kg (260.1 pounds)
Wet Weight119.0 kg (262.4 pounds)
Wheels & Brakes
Front Tire/Tyre80/90-21
Rear Tire/Tyre110/80-18
Front BrakesSingle disc
Front Brake Diameter260 mm (10.2 inches)
Rear BrakesSingle disc
Rear Brake Diameter220 mm (8.7 inches)
Wheels
Comments
Spanish brand.