Modified OEM mufflers

[Guest V11]

I don't know if anyone else has done this, so I thought I'd relate it if anyone else wants to try.

My V11 Sport came with what appeared to be two aluminium mufflers. Not bad looking, but too quiet for my liking. Not wanting to ruin the factory looks or spend lots of cash, I decided to modify the mufflers by removing the baffles. I removed both mufflers and discovered that the mufflers are actually stainless steel mufflers (sealed shut) with an aluminum cover. I guess that explains why they're so heavy....

Not willing to admit defeat, I whipped out the reciprocating saw, a cold-chisel, and a large hammer. After taking off the aluminum cover and thin sheet of fiberglass wrapping, I was staring at the stainless steel canister. At the engine side of each muffler, I made a cut up from the bottom until I was about an inch from the top (in effect, about cutting the thing in two!) I did a similiar cut at the exhaust end, but from the top down. I pulled out mounds of what looked like steel-wool and (by slightly twisting the muffler) a few pieces of pipe! Lots of stuff for a simple muffler. I then opened the rear of the canister up and put the fiberglass wrapping and aluminum cover back on----viola! A stock looking muffler that is much deeper and growls like you wouldn't believe.

It seems that in the stock system, the exhaust enters the muffler, goes through a smaller pipe all the way to the rear/ bottom of the canister into a small chamber. Inside this chamber, running from the front/top of the muffer is a perforated tube that exits the canister at the rear opening. All this means that the exhaust travels a long and sort of plugged up route through the muffler. Will all this cut out, the exhaust enters the canister and has nothing impeding the flow out.

[Guest Brian Robson]

This has been covered in some depth before, but it seems as though this route presents as an easy answer to a better sounding muffler.

Do have any pictures of your expedition?

Steve G cut open a flap and did a similar modification

[kjaj97]

The OEM mufflers have a lot going on internally. Here are few threads with pictures:

 

http://www.v11lemans.com/forums/index.php?...haust++pictures

 

http://www.v11lemans.com/forums/index.php?...haust++pictures

 

I cut the back 6" off my mufflers in search of the weight and performance benefit of aftermarket cans without the expense.

 

My bike ran well with no other modifications except the modified exhaust, but if you reduce restriction on the intake side (remove the air box lid/pods) you will need to richen the mixture via a PCIII or other means or the bike will run lean.

 

Welcome to the forum! - If you like to tinker with your bike, Ive found the people and information here are invaluable.