Crankshaft -QUATTRINI M232, stroke=57mm, connecting rod length=126mm (rotary valve)- Vespa Rally200, PX200, Cosa200 - for Quattrini M232

Quattrini M232 crankshaft with 126 mm connecting rod for PX200, Rally200, Cosa200

It is designed for use with the original carburettor and touring exhaust and yet already achieves over 20hp and a full 24Nm at the rear wheel. An original PX200 GS with 12PS/9kW registered in the papers rarely achieves more than 10PS and 15NM at the rear wheel.
60 % more torque and 100 % more power, combined with a very touring-suitable power delivery certainly fulfill more than just the dream of every Vespa rider.

A comparison for the very good rideability:

• The maximum power that an original 200cc engine delivers at 5700rpm, the engine equipped with the M232 package shakes it out of its sleeve at just 3500rpm!
• The maximum torque that an original 200cc engine can deliver at 4300 rpm is reached by the M232 engine at 2800 rpm, i.e. just above idling speed.

The M232 makes use of several technical tricks to achieve this:

• The cylinder does not have a cylinder base that protrudes into the engine housing
• The crankshaft has a 16 mm longer connecting rod than a standard shaft
• A piston that is chamfered at the bottom in the overflow area ensures maximum overflow area

Due to the missing base, a significantly larger piston than usual can be used. The extra-long connecting rod makes it possible to position the overflow inlets in the cylinder further upwards than usual. In conjunction with the special piston, which has heavily chamfered surfaces on the underside of the overcurrent inlets, this enables a very large overcurrent area without having to machine the engine housing. The long connecting rod with an impressive 126 mm connecting rod also improves the connecting rod ratio from lambda 0.26 to lambda 0.22, which is important for the smooth running of an engine.

At 57 mm, the stroke remains identical to that of the standard engine. This allows the use of a crankpin with a diameter of 22 mm due to the sufficiently large overlap on the crankpin. The crankshaft is therefore less susceptible to twisting of the crank webs. It also has a beautifully designed intake area and allows large cross-sections without having to rework the engine housing. If you enjoy getting more than the average out of your engine, you can significantly increase the power and torque of the set by adapting and enlarging the intake and using a larger carburetor. In conjunction with the BGM BigBox Sport, over 25 hp and up to 30 NM at the rear wheel are then easily possible. The power peak is then still at a socially acceptable 6500 rpm, but if required the engine can still develop over 20 hp at the rear wheel even at 8500 rpm.

Conclusion: Traveling or racing is no longer a question here, but an option.