Shimming Vespa & Lambretta transmissions
Here we show you how to properly shim the Vespa transmission: shimming Vespa transmissions
In order to balance out too much free play in the gear box you need shims in the corresponding thickness. We have introduced these high quality BGM PRO shoulder rings for Vespa and Lambretta engines to our programme.
The hardened and grounded transmission shims generally have a tolerance of just +0/-0.04mm and during manufacture each batch is subject to comprehensive testing.
Vespa shims/ spacers / shoulder rings
Vespa Rally, Sprint, VNB etc.
There is reason for enthusiasts of the older Vespa Largeframe models like the Vespa Rally, Sprint & Co. to be pleased: for these gearboxes, the fitting shoulder rings ranging from 2mm to 2.50mm are finally available again, thanks to BGM PRO.
The shoulder rings feature, as is the case for the stronger Vespa PX EFL version, 4 nibs for locking in. Hence, with the new production design it is no longer possible to chop off an individual nib.
We had the shoulder rings for the older 3 and 4 speed gearboxes (can be identified by the single shoulder ring that is required on the shifter bolt side) manufactured for you in standard dimensions.
- BGM6020S20 Gearbox shim -BGM PRO- 2,0mm
- BGM6020S21 Gearbox shim -BGM PRO- 2,10mm
- BGM6020S22 Gearbox shim -BGM PRO- 2,2mm
- BGM6020S23 Gearbox shim -BGM PRO- 2,3mm
- BGM6020S24 Gearbox shim -BGM PRO- 2,4mm
- BGM6020S25 Gearbox shim -BGM PRO- 2,5mm
Vespa PX EFL and Vespa Smallframe
For the Vespa PX EFL and Vespa Smallframe gearboxes we offer the shoulder rings in standard dimensions from 1.00mm to 1.40mm and additionally also in 0.9mm. This dimension is often required when converting the sprockets on the main shaft in order to restore the proper free play but also in case you wish to use the stronger circlips according to DIN.
- BGM6020S09 -Gearbox shim -BGM PRO- Vespa Smallframe V50, PV125, ET3, PK – Largeframe VNA, VNB, VBA, VBB, GL, Sprint, GT, GTR, TS, PX, Cosa, T5 – 0,90mm
- BGM6020S10 -Gearbox shim -BGM PRO- Vespa Smallframe V50, PV125, ET3, PK – Largeframe VNA, VNB, VBA, VBB, GL, Sprint, GT, GTR, TS, PX, Cosa, T5 – 1,00mm
- BGM6020S11 -Gearbox shim -BGM PRO- Vespa Smallframe V50, PV125, ET3, PK – Largeframe VNA, VNB, VBA, VBB, GL, Sprint, GT, GTR, TS, PX, Cosa, T5 – 1,10mm
- BGM6020S12 -Gearbox shim -BGM PRO- Vespa Smallframe V50, PV125, ET3, PK – Largeframe VNA, VNB, VBA, VBB, GL, Sprint, GT, GTR, TS, PX, Cosa, T5 – 1,20mm
- BGM6020S13 -Gearbox shim -BGM PRO- Vespa Smallframe V50, PV125, ET3, PK – Largeframe VNA, VNB, VBA, VBB, GL, Sprint, GT, GTR, TS, PX, Cosa, T5 – 1,30mm
- BGM6020S14 -Gearbox shim -BGM PRO- Vespa Smallframe V50, PV125, ET3, PK – Largeframe VNA, VNB, VBA, VBB, GL, Sprint, GT, GTR, TS, PX, Cosa, T5 – 1,40mm
The BGM PRO shoulder rings are hardened and ground parallely so that your transmission keeps the adjusted free play reliably and for a long period.
- hardened and grounded parallely
- just +0/-0.04mm tolerance
- available in many thicknesses
- for a precise gear change
- and a long lasting gearbox
Lambretta shims/ spacers / shoulder rings
For Lambretta gearboxes we can offer you transmission shims in different thicknesses as well. 
