brad black wroteyou need more flow area. the s4rs inserts are quite long - 150mm or so - and maybe 25mm diameter with the end capped. they have slots or a lot of holes along the side pieces and work very well. you might just need to use a std muffler, which at low sound levels will work better than a jammed up open muffler. maybe get some st or late ss series mufflers and mod them to fit, as you really want the latest ones you can get. they'll be heavy tho.
The small inserts I have tried are very similar to std Termi inserts which you can buy at the Duc dealer, but it is not enough for the nazi dB meter. What you see in the picture is app 150-200 mm long. Honestly, this is what is needed to pass the sound check in Sweden right now. (Next year you probably need an electric bike). Some guys with std mufflers on jap bikes have problems, then imagine the problems on a Duc.
The big mufflers I am waiting for are coming with a guarantee to pass the sound check. If it does not work I will have to look for std mufflers as you say. Heaven forbid, I don't have a fork lift so I dont know how to get them on.
Brgds
Henrik
