Random Changes in Exhaust Volume

[Pretzel]

Asking this in a non-specific forum as it doesn't seem to be particular to any 1 make or model of bike... (not even baggers, persay, but I'm curious!!)

Why does the exhaust tame itself down at random? I've got a set of the Vance and Hines baggers, and some days it's got attitude and growl, and other days it seems much tamer. My 900 used to do it before, as well, with the debaffled stock exhaust, and it has always puzzled me.

At first I thought cooler temps led to quieter exhaust sounds, but this morning's ride in the 50's seemed to be one of the louder days! Am I just nuts?

Well... ok... :crazy: I *AM* nuts, but... Somebody please explain!

[ringadingh]

Ive noticed that as well with mine, not sure what the answer is. It could be with just the wind direction and temp, as it seems to sound louder on the colder days.

[Loafer]

I think you will find the answer in this article, I'm too lazy to read the whole thing.
But my guess is that the temps and the humidity would make the sound change. (?)
http://en.wikipedia.org/wiki/Speed_of_sound

[Pretzel]

I could see that having effect over larger distances, but there's only a few feet between the pipes and the rider's ear. That article discusses a decrease in the speed wouldn't have much of an impact at all being that close (or so I assume), but the perception of the sound level changes quite a lot. I would also think that if temp/humidity was effecting the volume of the pipes, it would effect the volume of everything else as well, right? But all other sounds are normal...

Sometime, I could swear it's quieter on a day's ride, we stop to fill up, and afterwords it's louder again. It's just odd.

[ray2]

I have had the exhaust sound vary on all the bikes that I have had and I now put it down to the way I hear.

[old dog]

That's what the wife said

[jestephens]

I notice a difference with the octane level I'm running, ambient temperature, engine temp, fuel processor settings, etc. It all affects the fire, therefore sound :)

[mobandy78]

Pretzel, you're just crazy and hearing things! :crazy: :tehe:

My thoughts would be wind direction. It's going to carry sound either toward you or away from you, thus making your exhaust sound seem different. :shrug:

[redjay]

The exhaust note changed on my Voyager after Joes (Chuckster) air intake and Cobra CVT install.

[Monkeyman]

The exhaust note changed on my Voyager after Joes (Chuckster) air intake and Cobra CVT install.

I would hope so. :)

[Loafer]

I went for a ride yesterday, and I noticed a difference in the sound of
my exhaust. Then I realized I had left my hearing aid at home.

[ringadingh]

The exhaust note changed on my Voyager after Joes (Chuckster) air intake and Cobra CVT install.
A lot of that sound is intake noise added to the exhaust noise.