Crankshaft BGM PRO Touring 60mm Long Stroke for Motovespa GT160 (C09/M09)

High-quality forged crankshaft from BGM PRO for the large Motovespa engines with 160cc. Here in a special version with 3mm more stroke than so-called long-stroke crankshafts with 60mm stroke.
For installation, it is usually necessary to slightly enlarge the crankcase diameter so that the connecting rod has sufficient clearance from the crankcase.
The cylinder must be adapted to the longer stroke by corresponding shims (spacers) and possibly manual adjustment (milling/filing) of the inlet/exhaust ports to the longer stroke.
This allows you to perfectly fill the larger displacement with port timing angles selected according to your specific application. As a result, you get a significantly more powerful engine than with the standard 57mm stroke. Please note that the inlet port is controlled by the piston in Motovespa engines. Raising the cylinder (by using a thicker base gasket) increases the transfer and exhaust angles, but simultaneously reduces the advance and inlet angles. Therefore, please calculate the resulting port timing angles resulting from the installation of the crankshaft/spacers before processing the cylinder (there are corresponding online tools available for calculation).

CLUTCH OPTIONS
BGM PRO took the opportunity during the construction of the crankshaft to produce two versions of the GT160 crankshaft, which has been unavailable for a long time.

• Clutch type Motovespa (as original Motovespa for original clutches with cone)

• Clutch type PX (compatible with PX-type clutches)

Anyone who wants to build an engine with the original clutch uses the crankshaft for the Motovespa clutch type.

Anyone who wants to use clutch types other than the original GT160 uses the crankshaft for the PX-type clutch type. This allows all clutches that can also be used in the PX engines to be used without further modifications.

MATERIAL
The Motovespa GT160 (actually 160 GT) crankshaft is manufactured from high-quality forged blanks. The forged material is significantly denser and more resistant to bending, making it perfect for use as a durable and strong crankshaft.

BEARINGS
The lubrication of the lower connecting rod bearing is done via two large lubrication slots and a total of four additional pockets on the side. The SSC racing bearing and the side thrust washers ensure solid support. The lubrication of the upper connecting rod bearing is done via two lubrication bores. The INA piston pin bearing is included in the scope of delivery of the crankshaft.

CONCLUSION
All in all, the bgm PRO crankshaft offers the highest quality in every component. Precision in manufacturing, materials used and, above all, the precise balancing leave nothing to be desired. This guarantees an extremely smooth and vibration-free engine operation.

PORT TIMING/TUNING
With the original 57mm stroke, the original GT 160 cylinder has the following port timing angles:

• Piston clearance 0.5mm

• Intake angle: 131°

• Exhaust angle: 144°

• Transfer angle: 119°

• Advance: 12.5°

If the same cylinder is used with a 60mm stroke, the following port timing angles result:

• Piston protrusion: 1mm

• Intake angle: 132°

• Exhaust angle: 148°

• Transfer angle: 124°

• Advance: 12°

About the manufacturer BGM

BGM is a leading brand for high-quality spare parts and accessories for scooters, motorcycles and classic Vespa models, which stands for quality, precision and innovation. With a uncompromising "Made in Germany" philosophy, BGM develops durable products in collaboration with leading engineers and under strict quality control. Whether restoring classic vehicles or tuning modern scooters – BGM is the first choice for demanding drivers. Thanks to first-class workmanship and a wide range, BGM offers ideal solutions for performance, everyday use and individuality.