Gearbox (gear cogs incl. drive shaft) -BGM PRO- Vespa Smallframe, 4-speed- 58, 54, 50, 46 teeth, Vespa PK S, PK XL1, PK XL2, ETS, V50 (V5A1T from Nr. 69444), Special (V5B3T from Nr. 94315), Elestart (V5B4T from Nr. 1514), PV125 (VMA2T from Nr. 150203), E

bgm PRO Gearbox 'Made in Europe' for Vespa Smallframe

Fully assembled and precisely shimmed gearbox - ready to install.
Gear ratios identical to original.
Shorter, sportier ratio possible by simply swapping the secondary shaft (see accessories).

Extremely durable & precisely manufactured

For maximum loads, the gear wheels are manufactured in Europe from high-alloyed NiCrMo case-hardened steel (14NiCrMo13). The precisely machined base material is then hardened by Thyssenkrupp and is prepared for the highest engine outputs. To guarantee this, bgm gear wheels undergo extensive testing.

Tested quality – 90% higher load capacity

Pulsation tests at a German laboratory, where we compared the very strong original Piaggio gears with our bgm prototypes, showed a 90% higher load capacity of the bgm gears. The precisely defined surface hardness of 58-60HRC also makes the gears extremely wear-resistant. Better than Piaggio quality. Consistent high quality. No compromises.

Versatile application & compatibility

APPLICATION
Suitable for all types of use, whether touring or racing.
The gear ratios match exactly the original Piaggio gears. Additionally, a shorter 4th gear is available. The gears are compatible with all commonly used secondary shafts that are approved for use with stock gearbox parts.

GEAR TYPE 42
bgm PRO gears correspond to the latest version introduced by Piaggio from 1976 onwards. Commonly known as the PK gearbox, it was already used in ET3 models and V50 Special. Original gears of this new type are marked with a cast number/letter combination. PK type gears start with '42' and end with '/s'.
bgm PRO gears are also marked '42'.

COMPATIBILITY
bgm PRO gears fit all engines originally equipped with this gearbox type or already converted to it. For converting older engines/vehicles (pre-1976), a new main shaft is not required. Only the gears and PK-type selector cruciform (height = 50mm) are needed.

Converting 3-speed
3-speed engines can also be easily converted to a 4-speed gearbox with the appropriate selector cruciform (height = 50mm) and bgm PRO gears.

Austrian gearbox
Austrian small motorcycles have a longer secondary ratio.
Conversion to the bgm PRO gearbox is possible if the secondary shaft is also replaced. This gearbox was also used in vehicles for other markets (e.g. Portugal).

Exceptions
Vespa V50 1st series (V5A1T) with 1st series engine (V5A1M up to engine number 92876): These engines have a narrower engine case and a narrower main shaft. Conversion is not possible in this case.

CONCLUSION: Very robust gearbox components with excellent value for money