The Derbi GPR 125 is a street

motorcycle A motorcycle (motorbike, bike, or trike (if three-wheeled)) is a two or three-wheeled motor vehicle steered by a handlebar. Motorcycle design varies greatly to suit a range of different purposes: long-distance travel, commuting, cruising ...

sold by

Derbi Derbi is a manufacturer of motorcycles, scooters, mopeds and recreational all-terrain vehicles produced by Nacional Motor S.A.U., a Spanish subsidiary of Piaggio & Co. SpA. History Derbi's origins began with a little bicycle workshop in the v ...

- Nacional Motor since 2005. The original GPR125 was powered by a single-cylinder

two-stroke engine A two-stroke (or two-stroke cycle) engine is a type of internal combustion engine that completes a power cycle with two strokes (up and down movements) of the piston during one power cycle, this power cycle being completed in one revolution of t ...

with a steel lined cast iron cylinder manufactured by Yamaha, but was superseded in 2010 by an all-new

DOHC An overhead camshaft (OHC) engine is a piston engine where the camshaft is located in the cylinder head above the combustion chamber. This contrasts with earlier overhead valve engines (OHV), where the camshaft is located below the combustion c ...

four-stroke four-valve model.

Two-stroke GPR125

The engine in the original two-stroke model is sourced from Yamaha. This engine was used in the Yamaha DTR125 Dual Sport and TZR125 sport bike. Engine parts from these two bikes will directly swap with the Derbi. It uses the Yamaha Yamaha Power Valve System, a

two-stroke power valve system {{Unreferenced, date=February 2018 The two-stroke power valve system is an improvement to a conventional two-stroke engine that gives a high power output over a wider RPM range. Operation of a two-stroke engine A ''stroke'' is the action of a pis ...

, which consists of a rotary valve located in the exhaust port which changes the exhaust port timing and area. The power valve is controlled by an ECU and servo motor.

Four-stroke GPR125

In 2010 the engine was changed to a new four-stroke engine. The single cylinder engine features double overhead camshafts and four valves.

References

External links

Official website GPR 125 4T 4V
{{motorcycle-stub Sport bikes

GPR125 Adhesion G-protein coupled receptor A3 (ADGRA3), also known as GPR125, is an adhesion GPCR that in humans is encoded by the ''Adgra3'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Me ...

Motorcycles introduced in 2005 Two-stroke motorcycles