The float level of SI carburettors is not adjustable. If the float level is too low, the carburettor will buckle under full load and become dangerously lean. This can be caused by using a Cosa float chamber on a SI24/24E carburettor type of the PX models.

The float of the Cosa is lower and reduces the float level. The spacers offered here raise the float level to the correct level and allow a proper operation.

NOTE: We do not recommend the use on carburettors which still have the standard float chamber cover with float of the PX models (recognizable by the unsprung float needle with onlyØ 4.5mm instead ofØ 5.2mm of the Cosa). Otherwise the float level will be above the bore of the muzzle into the intake area with the consequence that the engine will be flooded with petrol. An exception are the standard carburetors of the Cosa models (24/24H). These can also benefit from the spacers, because the float level is also very low ex works.