Fuel tap -101 OCTANE- vacuum - for Aprilia RS 50, Derbi GPR 50, Mulhacen 125, Senda R/SM 125 - with tank sensor

Vacuum controlled fuel tap for Aprilia RS 50 06-, Derbi GPR 50 06- and Derbi Mulhacen, Senda 125cc 4-stroke manual mopeds.
Often a malfunction of this component leads to starting difficulties and engine misfires while riding.
The diaphragm of the fuel cock hangs and does not release the fuel or only to an insufficient extent.
The only remedy is a complete replacement