I know the limit there is 103 db at 50 ft, what I don't know is an accurate way to check to see if my bike is too loud beforehand. I have an '08 CBR1000RR that came with a Two Bros slip-on... it's not quiet. Two Brothers sells a db killer that they claim reduces noise by 7-8 db. I'm assuming that the bike is too loud as it sits, and also assuming the db killer should get it under 103 db... But before I pay for an event, load the truck up and drive 6 hours to get there, I'd like to have some kind of assurance. So who's been black flagged and what were you riding? Who's shown up with a bike they thought might be too loud and ended up being fine?
Not exactly what your looking for but I've been to NCM and Jennings with no problems with a full system and 14" muffler like in the pic. https://www.sportbiketrackgear.com/hindle-evolution-slip-on-exhaust-bmw-s1000rr-15-16/
here is the issue... there are a few exhausts out there that are known to be loud... but every single bike is diff.. I seen people get flagged for the "quiet" exhausts and ive seen people not get flagged with open pipes... it all depends.. sorry for the crap answer...my r6 was flagged at Jennings like 4 years ago for a 2bros .. but I just short shifted by the meter and no issues... (NCM they measure like everywhere so this trick doesn't work) then I went down there with an akra and never had an issue
when Stt was at ncm last year the guy on the exit of two left side of the bike was out with a DB meter bike is leaned to the right so my hindle on my zx6r had no issue passing
Did they tell you how loud you were? I'm assuming you weren't using a db killer? Any info is better than nothing.
I got flagged on my 07 GSXR 1K with the Two Brothers shorty GP exhaust and full headers at NCM, late in the day 2 years ago. Yes, it's obnoxiously loud. They said I was hitting 102.5 db. I had been riding all day (Staff) and had not set it off. I know where they sit and I wasn't short-shifting or anything. I questioned it, so I asked them to let me make a pass late and see if it was really me. I went out and gave it what for and tripped it again. Normally, that would be it - but because I'm staff and it was last session, i promised them I'd stay off it to get thru the rest of the day and they let me finish - and I didn't gouge on it at all during that session and didn't trip it. As to why it might go off some times different than others, the said the weather can influence how their test device works. I also have the DB killer, but it was not in on that day. I am convinced that the DB killer is enough to drop it under the limit. I ran it another month with the killer in it, as hard as I could going by them, and didn't trip it. Of course, if you know where they sit and short shift you MIGHT get away with it. Bottom line, put the DB Killer in (easy and doesn't take long) and you should be fine...of course, if the packing is old and burnt out, that might make a difference too....
My TLR was not Black Flagged last year.... And they had a DB thingy mcbobby at every station it seemed...
104 at Jennings... no db killer.. but as stated... if its humid or the weather is diff it can affect it... you should be fine with the db
I was black flagged last year with my Ducati Panigale/full Akrapovic exhaust. Put the DB killer inserts in and ran the rest of the weekend without a problem.