Iím on a mission to figure out how to make a quieter exhaust that looks better than stock. Hereís my plan.
Keep the stock headers and cat.
Replace the premuffler (breadbox) with a midpipe and use a generic muffler.
Use different baffles in different amounts and locations.
The generic muffler is solely because Iím going to make a quad muffler this winter and basically just want to test out how to best quiet it down.
Iím going to try to document every step and share what the differences are. Video doesn't do motorcycle exhaust sound justice as we all know, but Iíll do my best.
These are the parts Iím using:
eBay midpipe https://www.ebay.com/itm/123899278794
There are several options here. Some come with mounts for the stock exhaust cover and/or parts to weld your stock premuffler back on.
FMF fiberglass packing:https://www.ebay.com/itm/123881157894
Video 1. Removal of premuffler and testing different single baffle locations.
No baffle was obviously very loud. The power wasnít noticeably different, but the delivery seems less linear and the throttle input seems more abrupt. Good times for short periods for me personally, but Iím in search of a quieter option.
The baffle inserted into the muffler didnít have much of an effect on noise or power compared to no baffle. It did take off a couple decibels at idle but sounded louder while riding in the mid rpm range to me. It did take some of the off throttle popping down a notch too.
Putting the baffle in the midpipe was very quiet, but way too restrictive! It wasnít designed or advertised to be used there. The Z lost power everywhere. No power wheelies and after 5k it revved out very slowly. It was silky smooth with throttle input though. I imagine this is what a restricted motorcycle would feel like. Surprisingly, it didnít throw any codes.
Drilling out the baffle as seen in the video returned the power. This is quieter than the muffler baffle option and felt most like the bike did with the stock premuffler. The riding ďtestsĒ were pretty much identical if not better than the other options that didnít impact power. I might even conclude that this option has more middle range power than the other two with a comparable top end.
EDIT: The above was not actually true. I discovered later that the packing had blown out because I made it thinner to fit more easily. Iíll have the update in another video/post.