First, "high" is a subjective term. I've already stated that my desire is an exhaust louder than stock but not "unmuffled." I don't believe this has to be made an all or none issue and see no sense in building up strawmen and forcing the debate in that direction.
Second, it is your opinion regarding the purpose served. Sirens and horns are loud because that
gets people's attention, full-stop. The anti-sound crew should be arguing that more careful driving on the part of first responders is all that's needed, not more noise, but they don't because they concede the point: sound works.
Humans generally rely on just 2 senses to know about us on the road: sight and sound. Why effectively advocate removing 50% of their sensory input for detecting us in their midst?
My Tuono (100% stock exhaust at the moment) has a valve in the exhaust, Below 5500 the exhaust path is more convoluted and ends up being very -- almost "whisper" -- quiet; above 5500 the valve opens providing a straighter shot for the exhaust through the silencer resulting in more torque and, yes, a higher sound level. The switchover point is very clean and in 1st gear in city traffic it's easy to add a few kph and open and the valve and then lose a few kph and close it again with little change in engine RPM or vehicle speed.
I've got lots of anecdotal empirical (observation) evidence that people's heads turn more often when the valve is open than when it is closed, whether they're drivers or passengers in automobiles or pedestrians. Nothing else changed; engine speed & mechanical noise is very close, vehicle speed is very close, lighting doesn't change, the look of the bike stays the same etc etc. Just the sound level; people notice the sound and look to see from where/what it's coming, simple as that.
I don't believe you would, actually. I believe you'd just stick with your personal opinion and that's that.
If I was to offer up an "expert witness" for the defense:
"... “Loud pipes annoy people,” agrees
Brian Lowes, chief instructor at Roadcraft, a Vancouver-based advanced-riding academy that specializes in collision-avoidance techniques and upgrading riding skills. “And from a safety point of view, it doesn’t seem to be beneficial to have a loud motorcycle, because many times, the trouble is ahead of the rider—the guy turning left in front of you, for example—and loud pipes won’t help you then.”
That said,
Lowes concedes that loud pipes can help “sometimes”. If, for example,
they help riders get the attention of automobile drivers beside or around them, who tend to be in their own little bubble of oblivion, then at least the drivers know that the motorcyclist is there. They may not like the noise, and won’t necessarily do the right thing. But
in a car-motorcycle accident, the most-often-heard excuse is “I just didn’t see him.” ..." (
link)
you'd just argue he's wrong. As the article says, "
Trying to argue that loud pipes don’t save lives because they’re so annoying is ridiculous."
How many instances of people becoming aware of your presence due to sound would be enough to change your mind? How many accidents, lane incursions, pedestrians stepping out etc
avoided by virtue of being heard would make some additional sound "okay" with you?
That is not what I'm advocating and even though I suspect you know that you're seemingly going to continue to beat that strawman anyway. :/