Making Cobra exhausts milder

[Stilt]

I love my new Cobra exhaust at speeds below 60 or when just cruising (low throttle opening) at higher speeds. However, pulling up hill with WOT or passing at RPMs above 3500 they get VERY loud.  Too loud for me, and certainly too loud for my co-pilot.  I have some ideas as to how to make them more civilized and am very interested in your thoughts.  One idea is to cut some thin slashes on about a 45 degree angle in the baffels about half the way through and inserting (welding) some steel washers to set up some back pressure. This would allow for a smaller diameter exhaust passage followed by a larger chamber then another smaller diameter hole, and so on.  A couple of these transitions should breakup the sound wave front enough to somewhat mute the exhaust sound.  My problem is how many washers, what size and spacing.  Another idea is to enlarge the existing cuts in the baffels to make the baffel interior more rough.  Or maybe wrapping the baffel in some exhaust fabric.

Has anybody experimented with these or other approaches? Any other ideas?  Untill I can resolve my concerns I have reinstalled the stock pipes. 

[Thunderbolt]

the kind they sell for repairing your boat.  Wrap some around each baffle and wrap some stainless steel wire around the fiberglass to hold it on.  I did this to my Cobra's and it helped just enough to make it tolerable.

[RLD]

Buy another set of baffles, wrap both of them with muffler packing, and with a little work they will both fit. I had to notch the forward ones with a die grinder to clear some weld. It made a huge differnce in sound. At cruising speed, it was actually very quiet, but had a nice rumble when accelerating. I think I bought my second set from JC Whitney. It's been a few years now, and the pipes have long since been sold to someone else. I went back to stock as I have an I/s and do a lot of longer rides.