drilled in a non uniform way...in other words it's not pretty but it works. i first tried a 21mm hole saw i had and that just busted through the outer piece. so i bought a 1" bit that shanked down to 1/2" and finished it off. i wish i had started with the 1" bit.

 

Buff, curious what you did with that outer piece. hard to tell from the pic. does it look like you went into the SA chamber with that? I didnt fully get to that point but close. Damn hole saw bit broke, so i just driled a series of holes around it. sounds much better and much less back pressure. Was the part sticking out a mod you did i take it?

 

DO you have a picture of yours also? looking for ideas to finish and what it looks like if i dig further

 

I hacked off the end of the muffler, cut out all the baffles except for the last one before the core. I left that one so it wouldn't blow any flames, but I did take a screwdriver and open the louvers up a bit. I ended up with a nice tone out of that 4" opening. PM me a cell # and I will gladly send you a pic

 

i'll try to get some pics fro you mattyw, my bike is at my buddies house cuz last night i really ate it off a jump. everything bent back into place on the bike tho, and that's what's important.

 

hard to explain, but if you have a 2 bolt mounted end plate simply add a washer or 2 behind the plate and reinstall it. You'll get a little soot on your fender but it looks stock, isn't too noisy and breather a bunch better. If you punch or drill the inner core, don't go into the 2nd plate or it won't pass the Forest service stick test.

 

it is better to throw oem muffler away, they add weight to da bike.