Why are motorcycles so looud?

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tcsenter

Lifer
Sep 7, 2001
18,949
575
126
There is a guy who lives down the road a bit with a 1200 or 1300cc Harley. Engine is built to the max, with some kind of aftermarket pipes which are 10 times louder than factory Harley pipes. This idiot likes to run through our quiet residential neighborhood between 9:00pm and 10:00pm, revving the engine to 4K and 5K RPM, or gunning the accelerator under a heavy load. The house and windows vibrate and rattle.

I have no clue why these piece-of-sh-t contraptions have escaped federal and state decibel/noise limitations applied to every other kind of gasoline powered internal combustion engine. Your lawn mower can't disturb the peace but you can run up and down the streets of a quiet neighborhood at 2AM with a 747 engine on two wheels. Makes a lot of sense.

The police have been to his house two times in the past month from compliants. There isn't anything they can do about it, however, unless they catch him in the overt act of disturbing the peace.

Now he's doing it even worse to be spiteful, whereas he was only doing it for kicks before.

That's ok, though, things have a way of just happing to these kinds of idiots when the police refuse or are unable to do anything.

Honest, officer. I don't know who strung up that tiny cross wire across the road, just about neck level. What a shame.
 

OS

Lifer
Oct 11, 1999
15,581
1
76
Originally posted by: tcsenter
There is a guy who lives down the road a bit with a 1200 or 1300cc Harley. Engine is built to the max, with some kind of aftermarket pipes which are 10 times louder than factory Harley pipes. This idiot likes to run through our quiet residential neighborhood between 9:00pm and 10:00pm, revving the engine to 4K and 5K RPM, or gunning the accelerator under a heavy load. The house and windows vibrate and rattle.

I have no clue why these piece-of-sh-t contraptions have escaped federal and state decibel/noise limitations applied to every other kind of gasoline powered internal combustion engine. Your lawn mower can't disturb the peace but you can run up and down the streets of a quiet neighborhood at 2AM with a 747 engine on two wheels. Makes a lot of sense.

The police have been to his house two times in the past month from compliants. There isn't anything they can do about it, however, unless they catch him in the overt act of disturbing the peace.

Now he's doing it even worse to be spiteful, whereas he was only doing it for kicks before.

That's ok, though, things have a way of just happing to these kinds of idiots when the police refuse or are unable to do anything.

Honest, officer. I don't know who strung up that tiny cross wire across the road, just about neck level. What a shame.


I remember reading that HDs do meet state/federal noise regulations from the factory, but people often fit them with aftermarket exhausts. The thing is, the aftermarket exhausts are sold legally because they're labeled "for off road use only" or something like that. Basically the exhausts are sold under the pretense that they're not going to be used on public roads, but obviously they are.

You can probably videotape the guy and hand it over to the police. :p

 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
8
81
Originally posted by: dionx
the louder an engine is, the more inefficient it is. that said, harleys are real gas hogs
Uh? No? lol..

If anything, the quieter an engine is, the more inefficient it is. The more free the exhaust system is, the more efficient the engine will be. Mufflers typically cause a backpressure, and that's not good for raw performance.
 

kenrippy

Golden Member
Sep 3, 2002
1,763
0
0
What pisses me off is that when I ride my bike on the streets of CA, I have the fear of getting pulled over and receiving a ticked for a "modified exhaust". When it's in NO WAY as loud as the harley/chopper bikes out there. They seem to have no problems with those type of fix-it tickets. I cringe when I think of the work I'd have to go through to bolt on my old exhaust pipe and truck it over to a highway patrol or whatever to have it written off....cuz it wouldn't run with the stock exhaust anymore since it's been jetted etc. etc. After putting in half a day doing all that crap, the guy prolly wouldn't even look at the bike, just sign the ticket. /rant
 

BillyGoat

Senior member
Dec 29, 1999
430
0
71
cars generally operate between 1000-500 rpms motorcycle 1500-14,0000 rpm's
when i get my bike much up over 6000 they tend to get alot more audible
 

PowerMacG5

Diamond Member
Apr 14, 2002
7,701
0
0
Originally posted by: dionx
the louder an engine is, the more inefficient it is. that said, harleys are real gas hogs

wtf are you talking about? Motorcycles average way higher in mpg than any car (except hybrid or electric).
 

Novgrod

Golden Member
Mar 3, 2001
1,142
0
0
if there's one thing i learned from playing GTA vice city, it's that motorcycles are dangerous, dangerous stuff.

If you want to be careful with your life, don't get on a motorcycle. And leave my ears alone; they're just fine as-is.
 

silverpig

Lifer
Jul 29, 2001
27,703
12
81
Originally posted by: KraziKid
Originally posted by: dionx
the louder an engine is, the more inefficient it is. that said, harleys are real gas hogs

wtf are you talking about? Motorcycles average way higher in mpg than any car (except hybrid or electric).

That's partially because a bike engine has to push around ~600-800 lbs where as a car has to push >3000 lbs... Then there's the aerodynamic issues... You're not really talking about the same things here. You could say an electric gets an infinite number of miles to the gallon then cause it doesn't even use gasoline.

Loudness and efficiency are hardly related, but you can make a quiet engine more efficient if you take off the mufflers/exhaust systems as this reduces the backpressure. However, to say that a loud car is inherently more efficient than a quiet car is in error.

dionx is partially right though, but not for the reasons many think. Most guys with performance machines have engines that are very inefficient. These guys are also likely want to show off their power by fitting loud exhaust systems. So here you have a loud, inefficient car. On the other hand, some d00d in his stock chevy sprint gets great mileage, but buddy probably ain't gonna put no aftermarket pipes on these wheels, so here you have a quiet, efficient car. This is where dionx is correct.
 

mAdD INDIAN

Diamond Member
Oct 11, 1999
7,804
1
0
I don't know about you guys, but I love the sound that Harley's make. Of course, I've never had them go by my house, but I love listening to them on the road.

I did have a sportbike scream down my street though, I smiled when I heard the engine sing that sweeet sweet song.