DOPPLER gearbox for mécaboite driving DERBI euro 1, 2, 3 & 4

Here is the improved DOPPLER gearbox for mécaboite 50cc DERBI 6 speeds (Euro 1, Euro 2 and Euro 3 and euro 4 engine), it allows much more performance thanks to a better setting of the pinion (each report is reviewed).

This box is also revised in terms of the shape of the teeth in order to offer less friction, smoother passages, increased strength….

The materials used for the pinions are solid and resistant for push configurations or original engine.

The box is delivered 100% complete and pre-assembled, you just have to remove the origin and position it.

Characteristics of the reports of this DERBI 6V gearbox :

- 1st 32/13
- 2nd 26/14
- 3rd 27/18
- 4th 25/20
- 5th 26/24
- 6th 22/23

Mounts on all DERBI euro 2 and euro 3 engines, example :

APRILIA: RS 50 dal 2006 -> (DERBI D50B) - RS4 50 (DERBI D50B)
BULTACO: ASTRO 50 - LOBITO 50
DERBI: GPR 50 - GPR 50 Nude - GPR 50 RACING - GPR 50 racing dal 2006-> (DERBI D50B) - SENDA 50 DRD dal 2006-> (DERBI D50B) - SENDA 50 DRD R - SENDA 50 DRD SM - SENDA 50 EXTREME - SENDA 50 EXTREME SM - SENDA 50 R
GILERA: GSM 50 - H @ K - ZULU (2001) - RCR 50 - RCR 50 - SMT dal 2006-> (DERBI D50B) - SMT 50
VALENTI RACING: RME-SM (DERBI D50B)