Depending on the condition and use of your engine it may or may not puck oil out the breather due to blowby in the cylinders, catch tanks were designed so oil doesn't spew out onto the track. If you fit a crankcase breather filter to the tube or a modded tube it allows the crankcase to breath as it wishes but if your getting puking once the tube and filter fills up oil will spew on the track or road. Depending on your usage you may be better leaving it plumbed into the airbox that can also fill with oil if your puking oil. Or you could just run a pipe tp the reed valves and run the crankcase at negative pressure and excessive puking will just get blown out the exhaust onto track or road. Probably better you tell us what you do with your bike.