The Honda CBR 250 Chinese bike, specifically the Dongfang variant, is not an officially manufactured Honda motorcycle. It is a Chinese replica or clone of the Honda CBR 250. As such, there may be variations in design, specifications, and oil capacity compared to the official Honda CBR 250 models.
To determine the oil capacity of your specific Dongfang CBR 250, it is recommended to consult the owner's manual or reach out to the manufacturer or a qualified mechanic familiar with the bike. They will be able to provide you with accurate information regarding the oil capacity and any specific requirements for changing the oil in your motorcycle.