Complete special front cush drive sprocket assembly for Lambretta J50 + Lui 50 + Cento + J125 (i.e all 3-speed models) to convert them to a 4 or 5 speed gearbox!

The set consists of the following items:
1 x special bolt M348
1 x special sprocket inner sleeve X813
1 x sliding collar M344
1 x top cap M346
1 x spring M345

You have the possibility to add a choice of front sprocket, either 14, 15, or 16 teeth. Re-use your 3-speed dished washer B355 with this set-up.

This is the complete list of all possible front drive sprocket & clutch crownwheel sprocket combinations for all J-Range and Lui-Vega-Cometa models, complete with the required length chain (with 'live' product links):

45T Clutch Crownwheel Sprocket
45T clutch sprocket + 11T front sprocket = 73 link chain
45T clutch sprocket + 12T front sprocket = NO! 
45T clutch sprocket + 13T front sprocket = 74 link chain
45T clutch sprocket + 14T front sprocket = 74 link chain
45T clutch sprocket + 15T front sprocket = 75 link chain
45T clutch sprocket + 16T front sprocket = 75 link chain

46T Clutch crownwheel sprocket
46T clutch sprocket + 11T front sprocket = NO!
45T clutch sprocket + 12T front sprocket = 74 link chain
46T clutch sprocket + 13T front sprocket = stretched 74 link chain
46T clutch sprocket + 14T front sprocket = 75 link chain
46T clutch sprocket + 15T front sprocket = 75 link chain
46T clutch sprocket + 16T front sprocket = 76 link chain

47T Clutch crownwheel sprocket
47T clutch sprocket + 11T front sprocket = 74 link chain
47T clutch sprocket + 12T front sprocket = stretched 74 link chain
47T clutch sprocket + 13T front sprocket = 75 link chain
47T clutch sprocket + 14T front sprocket = NO!
47T clutch sprocket + 15T front sprocket = NO!
47T clutch sprocket + 16T front sprocket = 76 link chain