Lambretta Uprated Crankshaft Sleeve by CASA PERFORMANCE
This is a video describing why this product is such a great idea.
Casa Performance Lambretta drive sleeve upgrade kit.
Completely new design to keep the front sprocket permanently in place. Further advantages are the much easier assembly and the integrated puller.
The load - especially with very heavily tuned engines - on the screw to secure the front sprocket is very high and can cause it to come loose during operation. This is no longer possible with the Casa Performance solution. The sleeve is bolted to the crankshaft with a much shorter, high-strength screw (torque of 45 Nm.). The counter-pressure spring is held in place with a special nut via a solid 18 mm thread in the sleeve. It is not necessary to touch the teeth of the original drive sleeve with the pressure spring cover.