Loud pipes save lives! But on the track really loud pipes get you the black flag!
The organisers are strict with noise limits, but some days don‘t have limits.
If you get black flagged you’ll get one chance to make the exhaust quieter. Two black flags and its an early bath, UNLESS you have another bike spare!
Check the limits before you get to the track. Some tracks have drive by testers and other do a static test whilst stationary whilst keeping the engine at 5000 revs.
If its time to re-pack the exhaust, its best to do it before the event. Plenty of kits are on the market to do this.