The CNC engine case forms a solid basis for extreme performances. The guys have been working on this project for years and put the engine case to the test in countless races. By now they are ready to sell it. The engine case is CNC milled from solid material. The enormous crankcase provides enough space for the BSG full circle crankshaft with 90.2mm crankwebs. In order to increase the pre-compaction the cylinder base is equipped with no more than a slot in which the conrod moves. Of course this can also be enlarged. The bearing seats are designed for 52x20x15mm crankshaft bearings. Spacers for the crankshaft bearings are included. In order to achieve maximum performance, the crankshaft has to be exactly aligned.
The engine case comes with a 19.5mm screw-on spacer that allows of extreme transfer ports. Although you can modify the engine case to use a crankshaft intake, we strongly suggest the use of cylinders with direct intake. Suitable for all watercooled cylinders with 54-64mm Ø bore and 54-56mm stroke. e.g.: FALC, QUATTRINI and PARMAKIT. Karting cylinders (such as TM, ROTAX Ø 60mm) and CAGIVA or GILERA racing cylinders are currently used to achieve maximum performance. The engine case comes with a detachable shock mount that allows you to use rigid (drag racing) shock absorbers. Also the swing arm is detachable and provides enough room for 3.50-10 tyres. The gearshift arm is ball bearing mounted.
You can either use a conventional ignition system, or ignitions made by PVL or SELECTRA. Primary bearing, engine studs and other small parts are included in the scope of delivery. All other components can be taken from a PK engine. The engine case requires the use of a BSG crankshaft. The version with detachable cover allows of fast adjustments to the gearbox, while the engine is mounted. This way you stay flexible at 150-400m races.
The BSG crankcases are the most extreme tuning crankcases that we have seen for the Vespa Smallframe motor. They may seem relatively expensive, although if the extensive design and production processes involved are considered, entirely fair. A suitable set of assembly instructions are in the pipeline but regrettably not yet available therefore we recommend that only experienced mechanics accept this invitation into tuning heaven!
Conclusion : Hardly surprising that Stefano Scauri has achieved 48PS with this set up!
SIP-TIP : Do not forget to order suitable oil-seals and gasket material. The BSG produced full-circle crankshaft is essential, the transmission can be set up using the BSG primary drive cogs. A strengthened DRT transmission, BSG drive-shaft and clutch are recommendable. Peripheral components, such as a SIP clutch cover and rubber buffers etc, should also not be forgotten.