The main jet sounds blocked. Turn the fuel off, central bolt on the float (10mm spanner) comes out which allows you to either remove the main jet with a screwdriver (5mm max flat blade) or blow it out with air. The jet is above the screwthread that held the bowl on. Merely reassemble in reverse order
the non genuine are fine put one on my tech-clean 250 no problems, straight swop, do replace gasket & hose, and clean filter in tank.