Description
Polini is one of the big names in 50cc scooter tuning, and is also one of the leading manufacturers of tuning parts for Vespa, modern and vintage.Cylinders, intake manifolds, exhausts, air filters, carburetors, crankshafts and more - everything you need to boost the performance of your classic Vespa.
If your clutch bell is turning blue which is caused by overheating, or is otherwise looking damaged, warped, cracked or worn, or your clutch is starting to slip or you're experiencing jerky take-offs, it is about time to get a new one. Old / worn clutch bells shorten the lives of your clutch shoes considerably, warped ones cause clutch slippage.
The Polini Speed Bell Vespa ET2 / ET4 / LX / LXV / S 50cc is an excellent value for money replacement for the original part and for slightly tuned engines. Excellent heat dissipation, for consistent acceleration from bottom to top end.
Polini Speed Bell
The Speed Bell series from Polini includes all clutch bells for scooters and maxi scooters. There are the "classic" Speed Bell bells and the Speed Bell Evolution, which is an improved version of the Speed Bell.
The Speed Bell clutch bells ensure better cooling of the clutch so that it can engage reliably over the long term and the clutch linings also wear less quickly.
The Evolution version is designed for more powerful engines as it has larger openings for even better cooling.
The function of the clutch bell
Even though the clutch bells of scooters (centrifugal clutch) and clutch baskets of motorcycles (with multi-plate clutch) look different, their function is basically the same. What changes is the way they are actuated.
On a scooter or moped with a centrifugal clutch, when the engine revs up, the clutch shoes spread and engage the clutch bell and cause it to rotate. The bell then drives the transmission, which in turn turns the wheel.
On a motorcycle or motocross bike with a multi-plate oil bath clutch, the lined clutch plates engage the plain metal plates, which in turn drive the bell to rotate the transmission and wheel. When the clutch is actuated, the lined discs no longer engage the plain discs and rotation comes to a halt.
In short, the bell ensures that rotation is transferred from the engine to the gearbox and wheel.
Clutch bell: performance
With a tuning clutch bell, it is possible to improve performance or reliability.
Choosing materials like steel instead of aluminum provides greater durability. The heavier weight of steel also leads to higher inertia, which in turn can lead to higher torque. This is the case with the Hinson Momentum bell, for example.
A bell can also have cut-outs to improve cooling and thus prevent wear. Therefore, on scooters, you often find ventilated racing clutch bells. Also in motocross, some clutch bells have more cut-outs than others.
In summary, the weight and ventilation of a clutch bell affect the overall performance of the engine.
How to replace a clutch ?
| Clutch Bell Polini Speed Bell Vespa ET4 / LX 50cc / Peugeot | |
|---|---|
| Article no. | U250.003 |
| EAN | 8054705082689 |
| Weight | 0,62 kg |
| Series | Speed Bell |
| Brand | Polini |
| Product type | Clutch bell |
| Clutch diameter | 107mm |
