This bearing conversion kit enables the combination of a 200cc reed valve crankshaft with the large frame VESPA PX 80-150cc motor. The 5mm longer con rod (110 instead of 105mm) leads to a larger pre combustion area volume. The transfer ports are easily modified and when the piston lies at Top Dead Centre the piston skirt clears the transfer ports.
Enables the use of PX200 reed valve crankshafts: Flowed to bell shaped, stroke 60-62.5mm. The connecting rods’ difference in length has to be compensated for with a base gasket.
Conclusion: The combination of a crankshaft originally intended for use in a 200cc motor and a 125-150cc cylinder opens up a whole new world of tuning possibilities. A feast for all those who love to experiment with the wonderful world of tuning through port timing adjustment.