If you own a Vespa with up to 50bhp and want a virtually indestructible clutch that will sit under the standard Vespa clutch cover this could be something to put on your Christmas list.
Italian tuning house, BFA developed a clutch capable of handling up to 70bhp by reversing the way a Vespa clutch works. Instead of the outer basket rotating with the crankshaft, the inner basket rotates. This improves operation and reduces the amount of mass fixed rigidly to the crank.
SIP bought the clutch from BFA in 2019 and still have it made in Italy by the same manufacturers. But not everybody needs a clutch capable of handling 70 horses! SIP decided to develop a similar, more affordable 4-plate, nine-spring clutch capable of handling up to 50bhp (I think you’ll agree that’s ok for around 98% of Vespa owners).
Technical details at a glance:
- CNC-milled aluminium basket outside
- 12-pinion bolted with primary pinion
- CNC-milled steel basket inside
- 4 full pads type “Cosa”
- Bearing mounted pressure plate
- CNC-milled aluminium cover plate top and bottom
- 9 springs
- Clutch plates can be changed in situ
- Can be mounted with the original PX 200 clutch cover
According to SIP, the Supersport clutch can only be beaten by the original 5-plate BFA clutch.
This 4-plate version takes inspiration from the excellent Cosa clutch plates but uses SIP plates mounted on aluminium. This has made it possible to increase the number of plates both inside and outside the basket and increases the service life. Nine springs are used to provide contact pressure. The individual clutch parts are CNC-manufactured from high-quality aluminium to ensure high standards and lower weight.
Different versions
The clutch is suitable for original PX crankshafts or for aftermarket cranks with toothing similar to that found on the BFA 306. The clutch can also be supplied without the gear so the end user can choose a larger Z64 primary gear from the likes of BFA, Malossi, Polini etc.
Autolube?
The splined crankshaft stub cannot be used with autolube because there is no clutch washer with splines to suit the inner M14 diameter.
The original crankshaft version can be used with autolube. However, the protruding M5 countersunk screws can rub against the axle of the gear pump in the engine casing. You can work around this problem by grinding the axle of the oil pump to allow it to sit 0.5mm lower, or you can grind off the screw protrusions.
Price and availability
The Supersport clutch is available in various versions from 22-25 teeth. Stock will be arriving at SIP in mid-January and they cost around £252 plus VAT.
You can check out the various options and pre-order yours now from SIP Scootershop or your local SIP stockist.
