Clutch Friction Plates with high-quality backing material for the "Cosa" clutches on Vespa Largeframe models.
With the wide selection of modern Clutch Baskets available on the market for Vespa Largeframe models equipped with the “Cosa 2” Clutch, virtually all requirements can be met. Whether it’s a heavy-duty touring scooter or a racing scooter with 50PS, the Vespa Largeframe Clutch can be easily modified to function flawlessly under all conditions. The greatest performance potential here comes from CNC-machined, one-piece clutch baskets, such as the SIP Ultrastrong or the MMW Superstrong. The only area that might still cause concern here is the Clutch Friction Plates.
- Lightweight, durable backing material
- Compatible with original Cosa2 clutches
- Available with various lining materials
While there are a number of different clutch plates made from various materials that certainly have good properties, it is the backing plate that causes problems. It’s made of low-quality steel. This means that thin, soft, and heavy plates have to transmit the forces and rattle their way into the clutch basket when idling. If the basket is harder than the plates, the plates wear out very quickly.
High-quality Clutch Friction Plates use aluminum as the backing material. In addition, the tabs are reinforced. To use such linings in the clutches of Vespa Largeframe models, modified motorcycle linings—such as those from the Honda CR80—are available, or Clutch Baskets designed specifically for this type of lining are manufactured and sold. Unfortunately, these plates present new problems. They do not break in smoothly, and the Clutch is difficult to modulate. Furthermore, the plate itself is not as durable as the original Vespa Cosa 2 plate. Both issues stem from the larger inner diameter of the motorcycle plates. While this does increase the maximum transmissible power, the smaller friction surface reduces durability and causes the plates to engage more aggressively. Even with the dimensions of the original Cosa plates, power output of over 50 PS can already be achieved.
SIP Performance "COSA 2" Clutch Friction Plates
With the SIP Performance “ ” Clutch Friction Plates, state-of-the-art backing materials are now used in the Clutch Baskets of Vespa Largeframe Models. The friction surfaces are mounted on aluminum plates. The tabs that engage with the cutouts in the basket receive Reinforcement. As a result, the plates no longer suffer during idle due to the poor ratio of their own weight to the thin contact area at the edges. The force is absorbed over a larger surface area.
In addition, the overall weight of the Clutch is reduced, and the aluminum dissipates the heat generated during the break-in process more effectively. The “ ” makes the Clutch’s operation less susceptible to thermal issues.
Clutch Plate Materials
The SIP PERFORMANCE RACE "CR80" "COSA 2" is available with two different lining materials: "sintered" and "black carbon." The sintered material is a very high-quality and durable option for high-performance everyday engines. It offers a good balance between power transmission and break-in performance. “Black Carbon” is perfect for use on the racetrack. It is more heat-resistant and can be engaged with precision even at full throttle. However, it requires more pressure to transmit the same amount of force as the pads made of sintered material.
Advantages over conventional “COSA 2” pads
- less wear on the pads
- Lighter overall package
- Better heat dissipation
Advantages over motorcycle pads (e.g., CR80):
- Better break-in performance
- Less wear on the lining surfaces
Conclusion: The perfect complement to modern Clutch Baskets. Extends the service life of the linings, even in high-performance engines.
