The Derbi GPR 125 is a street motorcycle

Motorcycle

A motorcycle is a single-track, two-wheeled motor vehicle. Motorcycles vary considerably depending on the task for which they are designed, such as long distance travel, navigating congested urban traffic, cruising, sport and racing, or off-road conditions.Motorcycles are one of the most...

 sold by Derbi

Derbi

Derbi is a brand of motorcycles, scooters, and recreational ATVs produced by Nacional Motor S.A.U., a Spanish subsidiary of Piaggio & Co...

 - Nacional Motor since 2005. The original GPR125 was powered by a single cylinder two-stroke engine with a steel lined cast iron cylinder manufactured by Yamaha, but this bike has now been superseded by an all-new DOHC four-stroke four valve model.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, 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.