When an Italian manufacturer made for all, nobody will say this is a copy but if it's an Asian manufacturer, it's automaticaly a copy... except OS

Every manufacturers can made a copy or specific engine !

WEIKEN Racing works on this engine since one year, some people of ATOM come from GO and ARROW and it's not a secret that ARROW engines are made by GO and the ATOM too, but if you look the VORTEX, you can see there is lots of specific parts, the piston, sleeve, conrod, crankshaft, crankcase ( internal mould ), cooling head, needles of carburator, no suitable for other engines...