this is what my breather bolt looks like..why do you have to drill hole on uts side and block end ?

Yes mate block the end and drill hole into side of the bolt

my last post vanished or my ph is on Crack so why do you have to drill a hole in side of breath bolt and block front hole wont it breath as is thru the bsp fittings. .got an eboc can coming from states 

my last post vanished or my ph is on Crack so why do you have to drill a hole in side of breath bolt and block front hole wont it breath as is thru the bsp fittings. .got an eboc can coming from states 

my last post vanished or my ph is on Crack so why do you have to drill a hole in side of breath bolt and block front hole wont it breath as is thru the bsp fittings. .got an eboc can coming from states 

Because you drill into the air cleaner mount on the inside of the bolt head

With the factory set up the engine/carb actually sucks the oil out of rocker covers before it drains back to sump.

I have same setup as Ando on my Evo with a small vented catch can. Works well. Since installing catch can there has been not one drop of oil in catch can.

I would recommend a vented catch can. A piece of hose under the bike may become blocked and cause you some engine problems. 

ended up usin wimmer top filter ext breather set up but its a bit smokey lol while stationary and at low speeds after long run or on hot days .. bikes only done 5500 and its using 400ML oil per 4000KM..may end up removing top filters and replacing with wimmer cross over pipe and run hose into eboc can and run a line from breather port on eboc to vaccumm port on throt body