Reply To: [How to Tutorial] [Bike Mod] 650/250/125 – AiS Block Off Removal (EGR Delete)
Yes you can block those 4 holes but if the carb itself has a silver port expecting vacuum from air box, connect it back.
Also I am concerned the fuel filter is facing the wrong way (restricting the flow-speed potentially)
Also make sure the Engine Side is blank, so there is no hissing from the engine cylinders too.