PIAGGIO revolutionized the world of large frame motor transmissions with the introduction of the COSA II clutch. All the existing large frame clutch problems were solved almost overnight.

Since around 1995 the COSA II clutch has been used in all VESPA PX EFL/'98/MY /'11 and of course, the COSA II models build by PIAGGIO. It comes complete with 4 friction plates, 8 springs and a sturdy clutch basket design. Due to the higher pressure created by the increased number of springs and the increased frictional surface area power can be transmitted more effectively between the crankshaft and the gearbox. Precision laser-cut clutch plates prevent any problems with snagging clutches. No jerking, no slipping, an optimal release point and all that combined with a light, easy clutch lever action, even when using a stronger set of springs.

The gear cogs for the COSA II clutch are available with 20, 21, 22 and 23 teeth. The cogs with 20 or 22 teeth fit into 125-150cc motors and the 21 or 23 toothed cogs into the 200cc motors without having to also replace the primary driven gear cog. If, on the other hand, another primary gear cog or the DRT clutch gear cogs are used, more transmission ratios are possible. All VESPA large frame models since the VNA/VNB range up till 1994 can be fitted with the COSA II clutch. With these 125-150cc models the existing clutch cover must either be modified due to the largest size of the COSA II clutch conversion, or replaced with the clutch cover from the 200cc motor with a suitable pressure plate.

The traditional Italian manufacturers NEWFREN and FERODO have a version of the COSA II clutch available with a reinforcement ring welded around the outside diameter of the basket and also springs, stronger than the original items. This 'ringed' version should only be included in motors tuned up to around 15 PS. For all you original VESPA fans we also have the original PIAGGIO version in stock.

Helpful Hint: Regrettably the production quality standards of both manufacturers of this clutch system was not always consistent with the high quality we have come to expect from PIAGGIO & CO. We recommend therefore that these clutches only be used, in their standard form at least, in original motor setups. When a reinforcement ring is included, mildly tuned motors can also benefit from this clutch system. If however, the comfort that this clutch system offers cannot be done without - even in a highly tuned machine