Hi buddy, just got back to good old India, saw the picture you posted . My guess is that the holes are for a jig to hold the inner pipe in place while the exhaust is welded. The exhaust gases most probably are not supposed to make it till the hole but you have internal corrosion somewhere lower down the header and the gases are making their way back up to this hole.

BTW when we getting rain in Pune?

Prince bhai, any updates? Could you open up the silencer and check the pipe today?

sorry for replying late, i was not well for last three days.

so after discussing so much and even asking service centers it is not crystal clear why the hole is provided. apparently it is provided either for cooling or some condensation/vapours or whatever to evoporate.

in stock condition, these holes must not leak. i checked with some new/good condition pulsars. there is no opening in inner pipe, the holes are.in outer pipe only.

now coming to my problem. there was a big crack in the inner pipe. got it welded. and for additional safety closed the hole in outer pipe too.

Glad that your hole is finally closed,this was a very informative thread

Hahahaha

ROTFMAO
dude please clearly mention what you are tryinng to say...

@prince i know your problem is solved but i can think of the reason why ""HOLY" Holes of silencer " are because the silencer are Dual pipes
and if they have closed the outer pipe holes their can be crack of inner pipe (as in your case) and the carbon get deposited in they region between them and then they may act as a single layer...
and for dual pipe it may be because inner pipe has to be made enough thick and heat resistant so that they dont get damage easily and due to these properties it may look ugly and damage the look of the bike another reason can be due to heat and water(rain water or clogged one on road) it should not corrode fast .
hole will be there so as to get silencer cooldown faster...

These answers may or may not be correct as its just my thinking ...(i am not a Mechanical Engineer or designer)