One of my 2-stroke scooters is moderately loud, and I’m a bit self-conscious about it. I lay off the throttle when leaving my neighborhood (it still goes mamanaPOPmamenaPOPmamenaPOP all the way down the hill) but once I get on the city streets it’s go go go, baby. It’s also the zippiest of my scooters and an absolute blast to ride. Riders want a certain sound from their machines – my modern GTS Vespa goes from a pleasant purr to a smooth hum, the 2-stroke Vespa PX is more aggressive and throaty, and the Genuine Stella is the loudest. Anyone who claims their loud pipes are to alert drivers is kidding you or themselves. It’s not that drivers don’t hear you coming – you’d need a siren for that – it’s that they don’t see you because motorcycles don’t register “vehicle” in their brains.
Most of the noise is at low frequencies, where the wavelength of the sound is much longer than the diameter of the exhaust pipe. So I’d suggest the noise is not directional. Essentially, the pipe is creating a localized variation in air pressure, which propagates in all directions. Same principle as an omni-directional microphone (in reverse).
It’s a power thing, their ability to impose their will on you, they want to make noise and use the ‘loud pipes save lives’ as a trump card, shut you down, argument. The backwards direction is also saying that they are leaving you and you will hear it, you will experience loud noise just because it’s their will that you do. In that it is also a bit passive aggressive, they are being non-confrontational and getting their way over others.
*they are being non-confrontational and getting their way over others.
*
Thankfully they seem to be fading out. Often the junk cars they drove where I live were likely worth less money than they’d invested in the speakers and amps to make their useless noise. Or did it have a purpose I wasn’t aware of?
As far as to why motorcycle pipes don’t go forward is because it wouldn’t follow the lines of the rest of the bike. It’s that simple. Ever been to a bike show?
Phu Cat
yesh. I have a custom exhaust on my Dyna, but it’s not the obnoxious open pipes that some people run. it just gives it a bit more tone but is still street legal.
difference is, I’ll happily admit I installed it simply because I like the sound. I left the catalytic converter in place too since I very much like breathing and I assume others do as well.
Yes, coming up on 30 years: daily commuting except during hurricanes (which are rare in SoCal but we’ve had 'em before and they’d be welcome now to quench this drought).
I think your paragraph above is reinforcing my points. Nothing short of a siren will audibly alert drivers ahead (and even then it’s limited) and there’s not much point in alerting people you’ve already passed or who are coming up behind you and can’t do anything about.
[And most of the regulars around here are accusomed to my verbosity – and my penchant for emphasizing things with different colors (which I really tried to minimize in my recent screed.]
…and, yeah, let’s take lane-splitting to a separate thread if you wish.
–G!
…even rode my motorycle in the rain
And you told me not to drive
But I made it home alive
And you said that only proves that I’m insane.
[COLOR=White]…–Billy Joel
…You may be right!
…Glass Houses[/COLOR]
Well, I guess my main disagreement is saying there’s no point in alerting people who are coming up behind you. I think getting those people’s attention is absolutely critical. Defensive riding can mitigate much of the risk posed by drivers in front or beside you not seeing you, but for drivers coming up behind you making yourself conspicuous is your first and for the most part only line of defense. (Unless of course you can filter forward and so don’t ever have to be motorcycle sandwich waiting to happen.)
This has not been my experience; a loud-piped bike sounds much louder when you’re behind it than when you’re listing from other locations.