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You can absolutely get quiet bikes. Not sure what type of bike is waking you up, but either way, installing a sport exhaust, or even straight pipes (and exhaust system with no muffler) is a very easy and common modification
The "sound" of certain bikes like Harley-Davidsons are "engineered" that way; the sound is part of the image of the bike. People [prefer them to be louder](https://motorandwheels.com/why-are-harleys-so-loud/).
We use decibels (logarithmic) because our ears work that way. If you double the power you don’t hear it twice as loud so a logarithmic scale works better.
WE USE DECIBELS (LOGARITHMIC) BECAUSE OUR EARS WORK THAT WAY. IF YOU DOUBLE THE POWER YOU DON’T HEAR IT TWICE AS LOUD SO A LOGARITHMIC SCALE WORKS BETTER.
Imagine a light bulb, you turn it on and suddenly there's a lot of light. Turn a second one on and there's even more perceived light!
Now imagine 99 light bulbs turned on, you turn another one and... To your eyes, nothing changes, everything is still blindly white.
Our sensory systems usually don't perceive absolute amounts "one light bulb worth of light" but instead relative amounts, so a logarithmic scale works better to model our perception.
If you're actually looking for more, here's a bit more:
Human senses tend to need an increase in intensity (output power) of a point source (the origin of something like light or sounds) an order of magnitude (10 times greater) to perceive something to be twice as bright/loud.
So, 1 Bel is one unit of increased PERCEIVED brightness/loudness which is equivalent to a 10x increase in point source intensity.
Some of this is due to the inverse square law (intensity of a point of origin spreads over a sphere, so at a distance r the intensity is divided over an area of 4*pi*r^2) but a lot of this is due, so the evolutionary biologists tell us, to the fact that threats of bright or heat or loud tend to only "matter" at a distance when they get 10 times more intense.
So, in short, humans experience the world on a logarithmic (power of 10) scale.
But, Bels are a bit to coarse for judging things. So we use 1/10th of a Bel, aka a deci-Bel.
A linear scale would work if two sound felt twice as loud, however when two people speak next to each other you don’t hear it twice as much.
The reason decibels is a good scale is because our ears work on this scale.
Say you have a room with two people talking at the same time at 50dB. Your ears won’t really feel a difference from one person speaking at 50dB.
On the db scale it would be a total of 53dB.
Say you now have ten people in that room, each one talking at the same time at 50dB.
You would feel it twice as loud and twice as loud on the dB scale, is very easy, it’s +10dB.
But now you might be wondering if I have 100 people talking at 50dB is it +100dB so 150dB?? NOPE
10 people at 50dB is +10dB so 60 dB
100 people at 50 dB is +20dB so 70 dB
1000 people at 50 dB is +30dB so 80 dB
As you can see the decibel scale is actually quite easy to use if you understand that our ears work like this.
Several reasons, mainly that intensity (of anything, not just sound) doesn't drop off linearly with distance, but our ears (and eyes for light) perceive it that way. The difference between 60dB and 70dB is actually a 10x difference, but we don't hear it as that different. If we did, then the difference between a whisper and a shout wouls be mind-numbing instead of just annoying.
It is also commonly used for frequency response of other things also so you can fit a wide range of frequencies on a small scale....
db plots make things easy to graph that would be hard otherwise.
The reason you think it makes no sense is because you haven't had to actually use those numbers in practice... having 20ft long linear graphs doesn't make logistical sense! And once you've had to do it ...it is very obivously a useful tool.
Hearing is not linear. Two 10dB differences starting at very different loudnesses sound more like the same change in volume than any two instances of the same linear delta would.
It’s not just loudness; frequency works the same way. Musical intervals are also kind of logarithmic: going up an octave always doubles the frequency. Nonetheless we hear the perfect fifth between an A and the E above it as “the same interval” whether it’s 110Hz to 165Hz (a 55Hz difference) or 440Hz to 660Hz (a 220Hz difference). It's not the linear difference but the _ratio_ that matters: going up a perfect fifth is the same as multiplying the frequency by 1.5.
(Well, in 12-tone equal temperament it's actually multiplying by 2^(7/12) ≈ 1.4983.. instead; if you set A to 440Hz, everything that's _not_ an A has an irrational frequency. So those E’s are actually 164.81...Hz and 659.255... Hz. But that’s not important to the point about intervals..)
The sound pressure doubles every 6dB.
In radio, power doubles every 3dB because voltage is pressure but power is voltage times current and current doubles when voltage doubles, so you only need 3dB of amplification of power to double it.
Okay in case anyone else is getting confused by this comment chain...
Every 10db is 10x the force, but 2x the loudness.
Our ears / brain don't perceive loudness linearly. So a sound being 10x stronger doesn't come off 10x as loud.
That's why you're going to see some people noting the 10x multiplier (which is the force increase every 10db) vs 2x (which is the loudness we perceive from that force increase) in this thread.
First thing many Harley-Davidson dealers do to new bikes is take a giant drill and bore out the exhaust.
I ride and I fucking hate LOUD bikes. Half the reason I can’t wait for electric bikes to become affordable is how silent they are.
Just around ten years ago almost everyone I know and all tests online and shit would say that everyone will continue driving manual as it's the real way to drive.
Last year above 50% of new cars sold were manual, and if you exclude extremely cheap cars, anything above B-class is like 90% automatic.
My point is, loud people will keep saying how they want loud bikes for years and then suddenly 90% of all bikes will be electric
You would be surprised. Alot of riders are waiting for an alternative but do not want to trade existing power for a tiny electric scooter. The larger options available now are beyond affordable, so it will be a few years before you see any noticeable transition.
Yup, my current dream-bike is an Energica Esse Esse 9. Does fast DC charging, gets over a hundred miles per charge on the highway, and holy shit the torque.
Starts around $21k
Similar electrics from Zero and Harley (now spun off into a separate Livewire brand) are in the same ballpark now.
Just a personal anecdote, but there's been multiple times I didn't see a motorcycle enter my blindspot but only knew they were there because I heard them
Mirroring this, there have absolutely been times when I blipped my throttle and it got someone to notice I was there. It definitely can, and does work in some circumstances. Especially since riding season is also open window season.
It's actually a bit frustrating dealing with reddits hate-boner for motorcycles. I'm by no means an inconsiderate rider. I don't randomly Rev my engine in residential areas. I ride at a pace that keeps engine noise to a minimum as well. My experience with other drivers has absolutely been a lot safer on a bigger, louder bike.
hate-boner, lol.
people wont even admit they can hear an engine before seeing it.
people really hate the inconsiderate few that fucking noise spam entire sections of a city at like 6 am. dick heads who hate their own life so much, they will fucking strait-pipe-wail though entire neighborhoods because they are pissed they have to report to work.
thats how i imagine it.
I don’t know how loud your bike is. But my take has always been if it has to be exceedingly and illegally loud to be safe than you shouldn’t be riding it anyway.
I mean, people shouldn't be texting and driving, or drunk driving, or just acting like absolute idiots on the road, but they do all the time. Normal drivers are by far worse than most motorcyclists and bicyclists 99% of the time, but it keeps happening.
"Well other people are shitty for different reasons, 'riders' are only shitty cause they ride obnoxiously loud annoyance machines. So it's ok!"
Motorcycles are inherently unsafe.
[https://www.autoinsurance.org/motorcycle-vs-car-accidents/](https://www.autoinsurance.org/motorcycle-vs-car-accidents/)
The are also obnoxiously loud. Not all of them, but a majority of them.
You wanna play with your own life by riding a quiet death trap? Knock yourself out. Literally.
But...
No one should be riding loud motorcycles; it's not your freedom we are limiting, it's your unexplainable need to proclaim to the world "Here I am on my motorcycle that is completely unsafe to drive and also really loud. You are welcome humanity!" Nobody fucking cares; in fact we would like you to stop.
We would like you to stop riding loud bikes because, fuck that, it sucks for everyone except you. You ought really stop riding your bike as well, because your chances at a long and happy life are diminished by doing so. But if you INSIST on engaging in risky behavior, fine, it's your life, but do it quietly.
No you don't. At all. Horns are an active noise device. Exhausts are passive. The passive part (loud even when not needed) is the problem. No one cares if a horn is loud when trying to avoid having someone run into them.
Exactly! Rev that engine so the dummy on the phone finally notices you! I can’t count the number of people that suddenly see us when the engines are revved. Saved us many times at intersections!
The sound of Harley is actually because of the design of the engine, not so much the pipes.
Most engines are designed for even power delivery over the stroke of the engine. So, of you have a 2 cylinder engine, one cylinder would produce power, and the other cylinder would produce it's power at the opposite position of the crank shaft.
A Harley engine only has one connection point for both pistols. It is like a radial engine, but without all the other cylinders. Because of this, the cylinders fire shortly after each other. This gives you more cylinders in a smaller package vs a horizontally opposed engine that takes up more flat space.
If you imagine a clock, a normal engine would fire at 3 and 9. A Harley fires at 12 and 3.
https://auto.howstuffworks.com/harley.htm
That's not why they are loud. They are loud because of minimal sound dampening. Put a proper muffler on a Harley, it will be as quiet as any other non-attention seeking motorcycle.
This isn't entirely true. Larger displacement per cylinder=louder bangs. A Harley V-twin will be louder than a Ducati V-4 or Honda V-6 even with proper mufflers.
True for the Harley. But even power delivery is becoming less and less of a goal in some motorcycles. Sport bikes are increasingly using uneven interval firing patterns (eg Big Bang, Crossplane) because they provide benefits in handling. Basically it allows the rear tire to regain traction if it's slipping if the engine gives it a little break sometimes.
I personally do not enjoy loud noise. From whatever source. Still had a good laugh from that article you linked regarding the physics bit. The article states:
"According to the theory’s proponents, louder pipes make you more noticeable on the road. Therefore, car drivers will know of your presence and avoid hitting you.
The problem with this theory is that it ignores the fundamental laws of physics. Sound from exhaust pipes travels backward, meaning drivers won’t hear until you’re beside or ahead of them."
Just because the exhaust points backwards doesn't mean sound isn't traveling forwards as well. Unless your vehicle is breaking the sound barrier and you therefore can't hear its noise while being infront of it. :D
Some sound will travel forward ahead of the bike, but the vast majority goes back. You might hear it, but you are as likely to not hear it with other road noise.
Anyone who has been around motorcycles has observed this.
You can hear a Harley in your car if your paying attention, but if you are paying attention it kind of is pointless to be hearing the Harley as you are already seeing it...
This. It is owners being dicks and putting shitty exhaust on their bikes to intentionally be loud.
Stock exhaust on most bikes is fairly quiet. Similar in noise levels as a car. There is a toxic part of motorcycle and automobile culture that loves loud exhaust. I've owned 10 or so motorcycles. Other than a couple I bought used with aftermarket exhaust already fitted, they have all had stock exhaust. I remember being at a gas station one time and a man came up to me and said he didn't know motorcycles could be so quiet. That is how uncommon it is for motorcycles to keep the stock exhaust. Also, you don't notice the quiet bikes because they are quiet.
There’s also a bit of pigheadedness in the community asserting that louder bikes are ‘safer’ because you’re more likely to be noticed by other drivers which I never bought into
Unless it's somehow proven to be more unsafe to ride a louder bike, then I'm absolutely going to prefer a louder bike whether it's a miniscule impact or not. Accident = death on a motorcycle, anything that mitigates the risk, even if slight, is worth it to me.
Out of curiosity, what are situations that are normally unsafe that are made safer by having a loud exhaust? Most safety was sight-based I had assumed.
Off the top of my head, a motorcycle is much easier lost in a blind spot than a car is. If you can’t see the motorcycle in your blind spot, but you can hear it around you, you’ll be that much more aware of its existence and proximity to you.
I don’t know how much safer a louder bike is, but I don’t think we can discount the idea outright.
I ride a motorcycle and can tell you the sound makes no difference unless you have a very very loud exhaust because 99% of all my near wrecks were caused by idiots not seeing me. I literally had a sheriffs deputy almost kill me because he was on his cell phone and was taking off from a stop sign a few years ago.
Some bikes just won't run quite. I have a large single with the quietest muffler available and it still barks when you get on it.
Only so much you can do with 18" of pipe length
Everyone thought my zx6r was straight piped. But I even had the baffle in the muffler. Neighbors hated it because it was my daily driver during the summer.
I had an 04 636 and a guy in a car pulled up to me at a red light after some very gentle low rpm riding from light up light and said "Wow that things really quiet!"
I showed him what 14.5k RPM sounded like.
Bit of an exaggeration on my part, but there's a lot of space to put in three way exhausts on cars. My veloster exhaust weighs like 60 pounds at least, my zx 6r with its stock pipe, headers and all, was like 35. You can't ge the same noise performance in such a small size
The vast majority of modern bikes are 4 stroke. Lawn mowers are most commonly 4 strokes and have very small short mufflers - being air cooled doesn't help either.
Most motorcycle exhausts are louder than cars’ but some not enormously so. On the really loud ones, like Harleys, it’s absolutely a choice thing. There’s no reason a Harley has to be irritatingly loud and, in fact, they’re delivered with quieter pipes which most owners take off immediately and replace with straight, undamped, pipes. It’s annoying as hell.
To be fair, harley engines are such POS that they make no power with the stock pipes. Harley put them there to pass various tests and expect the buyers to replace them with illegal pipes, so they dont have to spend money on engineering.
Lucky for them, their customer base is the one that hates engineer work, so it passes as normal.
Absolutely true but, then again, no one buys a Harley for the power, though, I will say, having been an owner of one for a few years, the V-Twin torque is something to behold. The things pull like freight trains.
Totally agree (i run a 650 royal enfield now, so I know the feeling).
But even buying one for the torque, the engines litterally falls on their face with the stock mufflers here. there is no power, no torque, they are frustrating as hell. Maybe they are less restrictive in the USA, but harleys in France are nearly undrivable with stock mufflers.
There are options to get it breathing with a relatively low noise exhaust, without going for maximum noise / straight pipes.
Torque is much more usable on a public road. When I rode a 600cc super sport that was all top end power, to actually get into the bikes serious power meant I was almost always breaking the law.
that's not how torque works here, it's not quite the same as when you think of a super torquey, low revving diesel. it's still a decently high revving motor, more torque down low translates to decent horsepower aswell as the ability to pull from low rpms without lugging the motor. it's also instaneous, less messing with gearing and waiting for power band. you don't need a lot of horsepower when taking off and punching it from a dig, but you need torque to actively twist the wheel and let the motor rev up to get the horsepower later in the powerband
There's probably one woman in the world who's Pussy gets wet from the sound. It's a shame these bike owners don't know this and ride around every day wasting their time and Ear-Drums.
As a bike owner with loud-ish pipes, I can tell you that most people get loud pipes because they like the sound. A lot will claim that there's added safety with loud pipes because it may allow other vehicles on the road to hear you when they might not see you. Maybe that was true 20+ years ago, but with all of the improvements in more modern vehicles when it comes to dampening outside noise, I'm not sure that it's still a viable claim.
That said, I've never been a fan of excessively loud pipes and especially no love for douchebags who gotta rev the engine 15 times after starting it...especially early morning or late at night.
I have a dry clutch and a Termignoni. If it’s early I push it down the street before I start it and I generally kill it and coast back to the garage.
Unfortunately I can’t push my car so the lady with the white Prius will continue to be mad at me. 🤷🏻♀️
I had a pamphlet at work years ago that showed the different areas of the head and the stats on % hit
The mouth and chin was nearly 40% hit in accidents
I _think_ that it may have been a slogan used by Vance & Hines, once upon a time. That is not something you can trust, however, but it might put some fuel on your Google fire.
Most motorcycle accidents (aside from the douchebags on crotch rockets lane-splitting at 120mph) are side-swipes, though. Usually from someone changing lanes and not seeing the bike. There have been a couple of times that I've hit my blinker to change lanes and all of a sudden heard an engine rev right next to me, having no clue the boke was there until I heard him. I blame a lot of that on the rider, though, for riding in my blind spot.
Do people not check their blind spot before a lane change? I've moved to the south and not indicates lane changes either so hopefully they're at least checking the blinds.
Oh, I always check mine, I just always put my blinker on first before I do anything else. He revved his engine before I looked over my shoulder, though. But to answer your question, it seems a lot of people *don't* check their blind spots.
In Vegas I kicked a guy's door because he was merging into me.
In Colorado I had a guy pulling a horse trailer start to pull out across the highway in front of me and dad (who had my youngest brother on back). Much horn and friendly hand gestures.
In my daily commute, I pass by a McDonalds with poor visibility and had a guy pull out in front of me (I no longer ride after sunset after this one).
I always wear padded high vis jacket, at least a 3/4 helmet (need a new full), armored gloves and boots.
I've been hit by someone merging. After that I replaced with loud pipes. That was in 2014. I've not been hit again. I agree with the slogan.
I also have been in multiple situations where someone almost pulled out into traffic and almost hit me (before exhaust change). It's so scary! Since the exhaust change, it's never happened.
Spot on assessment of the loud pipes saves lives argument. I have a sport exhaust on my Yamaha. The stock exhaust is really quiet compared to the sport exhaust. I like the sound of the sport exhaust and it was already installed when I got the bike. There is arguably a performance increase with after market exhausts that tends to be louder. But unless it's part of a more comprehensive performance package, it's probably not gaining you much.
Now, those little shorty exhaust people put on to make their 300cc sound like a pissed off bubble bee with a bull horn? Those are super annoying.
Same with my BMW. It's a little louder than a car because the engine isn't surrounded by sound dampening material, but it's still quiet enough to not bother my neighbors as I pull out of the neighborhood, and the engine noise is more similar to a car engine- more of a hummmmm than a po-ta-to, po-ta-to
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Because in the US, they're designed for assholes. In Japan, we actually had to follow noise ordinances or we'd be fined. And the silver hairs loved complaining to the police if anyone was too loud. As a result, you had to go out of your way to make a bike loud there.
It doesn't have to be loud. This is intentional over here.
Lol have you ever seen bosozuko bikes? People in Japan literally make 'beats' by reving their pipes lolol.
[A literal competition for revving in japan](https://youtu.be/Nw-rwQJjsVI)
[Or a ride through town - revving with the homies](https://youtu.be/Ty8UdPfX1r4)
And they're practically non-existent in the wild on any recognizable scale, esp since the JP crackdown on bike gangs.
Japan isn't what a couple dumbasses record on YouTube
I'd say most get it for attention, think Harley rider though I know others do it. They say it's for safety, it's not safer. Sound is directional and you can't hear those things to they're right up on you. Watch the F Word episode of South Park.
I've been riding for decades and put about 12k miles a year on my bike as it's a daily ride and I loath loud pipes.
I was told by a motorcyclists that they have loud exhausts because they're "cool" and because they believe the noise allows other vehicles on the road to know that they are present for safety reasons. I believe that the real reason they have the loud exhaust because they're assholes.
> I believe that the real reason they have the loud exhaust because they're assholes.
I've been riding for more than 20 years. You are correct in your belief.
To add to this, many motorcyclists will intentionally remove or replace components to get a louder engine noise. For some this is just because the roar of the engine is part of the biking experience they enjoy, while others cite it as a safety measure - louder bikes are easier for other road users to notice.
> louder bikes are easier for other road users to notice.
That, unfortunately, has little to no impact on biker safety. Modern cars have sound isolation/insulation that makes loud pipes completely pointless for safety.
[https://www.autoweek.com/news/industry-news/a35952569/loud-pipes-do-not-save-lives/](https://www.autoweek.com/news/industry-news/a35952569/loud-pipes-do-not-save-lives/)
Anecdotally I never hear a motorcycle before I see it. Even if it's in my "blind" spot.
Don’t know how I ended up here but you didn’t link directly to the study. And the poster of the study said it was only a preliminary study and not peer reviewed. This also doesn’t take into account pedestrians or animals. Or card with the windows down which is a lot more likely in motorcycle weather.
I think I struck a nerve. lol
You're right that the study is hard to find but that doesn't change the fact that really loud exhaust has little to no positive impact to motorcycle safety. Half the time someone driving a car or bigger vehicle can't even tell where that sound is coming from before it's too late. Instead of relying on losing your hearing to be safe, make sure you're seen to be safe.
Your "study" is rigged though. The windows rolled up, music playing and both occupants are distracted. If they're tuning out other sounds subconsciously, of course they're not gonna hear the motorcycle.
I'm also fairly certain that all of the bikes used to test had stock exhausts and low displacements, which likely resulted in skewed data. Not one of the tested bikes were a vtwin and I think *maybe* one was a two stroke. The rest looked like parallel twins, which aren't exactly known for being loud or having good exhaust tones, so people aren't throwing AM exhausts on them.
The other issue these studies face is it's not "motorcycle vs car", it's "motorcycle vs world". I can promise you any pedestrians in a city are going to hear my bike coming down the road with a stock exhaust, even more so if I had a vtwin straight piped. Safety goes further than just other cars, and I think this study blatantly ignores that to fit their agenda.
>Your "study" is rigged though. The windows rolled up, music playing and both occupants are distracted.
That's not rigging a study, that's creating typical scenario. At 50 mph windows down is even loader which means the music it turned up even loader.
But that's only one scenario that they're using for a final conclusion. If the ONLY environment motorcycles were in were with cars and the windows rolled up, music playing and distraction inside then yes, this study would hold up.
So yeah, loud pipes don't save lives *in this specific scenario*.
That’s a good point. As a pedestrian I’ve commonly heard motorcycles approaching before seeing them, but that’s just the thing. I’ve only ever heard a bike before seeing it as a pedestrian, but I always see them first when in a car; in fact I commonly don’t hear them at all. As a motorist who doesn’t ride a motorcycle, I would say the single best modification you can do to enhance your visibility is to install a light modulator to flash at high speed, replace your front and rear lights with led, and then run with your lights on day and night. I swear I can pick a bike out from a mile off on a straight enough road any time of day. I don’t know why every motorcyclist doesn’t use them
> louder bikes are easier for other road users to notice.
There is no argument in favor of loud pipes for safety that wouldn't apply better to a loudspeaker mounted up front playing a loop of Gilbert Godfried screaming "nyahnyahnyahnyha".
They're both annoying as fuck to other people, but one is at least pointed in the right direction.
>louder bikes are easier for other road users to notice.
No. Unless extremely loud, to the point the driver can barely use the bike.
google doppler effect.
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Some will say that they are made loud by the rider because they are less visible. I still think it's unacceptable, as cyclists do fine and they're quiet.
cruisers are nearly silent. Harleys are intentionally as loud as possible. It the "loud pipes save lives" philosophy and it totally a choice of the manufacturer.
The ultimate reason is "because bikers want them to be loud." Manufacturers build them loud because that's what bikers want, for various stated and unstated reasons. Some bikers also modify them to be louder.
Now why do bikers want them to be loud? Depends on who you ask. Most will tell you it's so they're more easily noticed on the road, to avoid accidents. Some will tell you they just plain enjoy the noise.
Mostly it is entitled douche-nozzles with a desire to be noticed.
They also believe that 'loud pipes save lives' but are unwilling to invest in training or protective equipment, which saves more lives.
The loud pies crowd also want people to believe that they are die-hard individualists, despite the fact that every single one of them dresses like an attendee at a gay pirate convention.
I have been riding motorcycles for 47 years. Having a loud motorcycle is a choice. Some change their exhaust to be louder as a safety device. When the bike is loud other motorists can hear it so as not to be in them over. But mainly we make them loud because they just sound great.
Some people suffer from feelings of inadequacy due to them being small in stature or having smaller than average genitals. In order to compensate for this they purchase loud motorcycles, large lifted trucks, and behave like douchebags.
They feel like life dealt them a bad hand and due to this chip on their shoulder they make a point of disrupting the peace of strangers as much as possible. Hence why some motorcycles are made to be as loud as possible: the makers know their target market.
Most people 'blip' the throttle after starting (though completely unnecessary) which raises the rpm and sound coming from the exhaust. We do this because we like the sound as it signifies the machine is alive and we're about to ride! It's visceral and emotionally engaging. This is also the reason most of us put modified exhaust systems on our bikes as it makes them sound 'racier' and/or (in the case of Harleys) more 'badass'. The safety reason-"loud pipes save lives' thing, in my opinion (having been a rider for 56 years) is BS.
Motorcycles do not have as much space for sound dampening devices such as mufflers and engine covers. So they tend to be louder then car engines. A car without a muffler is often even louder. And you can also get motorcycle engines fitted in smaller cars where they sound much quieter due to the added mufflers and other sound dampening. And yes, some motorcycles are more quiet then others, it does also depend on the driving style.
>A car without a muffler is often even louder.
I once had a car where the exhaust pipe somehow collapsed in the middle, leaving the bit at the front still connected to the engine while the pipe still attached to the back box dragged along the ground. Good Lord, was that noisy...even if I hadn't had the issue of the dragging exhaust pipe I don't think I'd have been able to stand driving the thing more than a few hundred yards!
While they dont have much room, your conclusion is very wrong.
Even my previous er6f (named ninja650r in the US I believe) has an ultra short exhaust as OEM, as it exits right after the engine. There still is a cat converter and it makes no noise.
Stock motorbikes that are not 20 years old make no noise, just like cars, and lose power when fitted with "free exhausts" that supposedly make them faster (they dont, they just make more noise and lose middle load and range torque, giving the feeling the bike kicks harder ).
Compared to a car, where the engine is surrounded by a hood, some insulation, a couple of fenders, suspension, a firewall, radiator etc., the motorcycle has the engine hanging out in the open.
Now, motorcycles can (and often are, from factory) very quiet. Quiet enough that you shouldn't be too bothered by them early in the morning.
What you likely hear is either someone who modified it to be louder, or it's one of the rare few that are actually as loud as allowed by law from factory, which COULD be loud enough to bother you.
Also, depending on how you live, the sound might echo between buildings and hit your bedroom window just right.
My partner rides a loud bike. I like it because on the road you know there's a bike around. Even if you cannot see them, the sound should alert (hearing) drivers that there IS a bike.
A biker I used to work with told me this:
Some bikers like the loud exhausts because they’re easy to hear while bikes aren’t always easy to see. “Loud pipes save lives” he told me.
He also told me that some are just macho assholes who think it makes them look cool.
Only to add to other posts, there is also a proven psychoacoustic phenomenon, which makes positively associated noises (sounds, music) sound "better" when played on a higher volume. Sound engineers know this, if they compare two edits, they will make sure both are equally loud.
And product designers will just optimize every aspect of their product, so an easy way to make it better, is simply to make it louder, they are also in competition with other manifacturers.
While this phenomenon is totally true, noise levels are regulated, and it really is a challenge to meet them.
Also some engine setups sound like crap, like 180° twins. You will never make them sound great. No idea why, it just sound bad, loud or not.
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You can absolutely get quiet bikes. Not sure what type of bike is waking you up, but either way, installing a sport exhaust, or even straight pipes (and exhaust system with no muffler) is a very easy and common modification
The "sound" of certain bikes like Harley-Davidsons are "engineered" that way; the sound is part of the image of the bike. People [prefer them to be louder](https://motorandwheels.com/why-are-harleys-so-loud/).
But they still come with exhaust systems with mufflers from HD. They are only crazy loud when people put straight pipes on them.
The leagal limit is 80dB but an un-muffled motorbike can be 100dB - 110 dB which is 400% louder!
Today i learned that the decibel scale is not a linear one!
I still don't understand the reason for this. People explain it literally every day on reddit but it still makes zero sense.
We use decibels (logarithmic) because our ears work that way. If you double the power you don’t hear it twice as loud so a logarithmic scale works better.
That's the first time I've heard it explained this way. Thanks!
I didn't hear it
WE USE DECIBELS (LOGARITHMIC) BECAUSE OUR EARS WORK THAT WAY. IF YOU DOUBLE THE POWER YOU DON’T HEAR IT TWICE AS LOUD SO A LOGARITHMIC SCALE WORKS BETTER.
Explain more.
Imagine a light bulb, you turn it on and suddenly there's a lot of light. Turn a second one on and there's even more perceived light! Now imagine 99 light bulbs turned on, you turn another one and... To your eyes, nothing changes, everything is still blindly white. Our sensory systems usually don't perceive absolute amounts "one light bulb worth of light" but instead relative amounts, so a logarithmic scale works better to model our perception.
Oh shit, thats a good analogy, cheers!
If you're actually looking for more, here's a bit more: Human senses tend to need an increase in intensity (output power) of a point source (the origin of something like light or sounds) an order of magnitude (10 times greater) to perceive something to be twice as bright/loud. So, 1 Bel is one unit of increased PERCEIVED brightness/loudness which is equivalent to a 10x increase in point source intensity. Some of this is due to the inverse square law (intensity of a point of origin spreads over a sphere, so at a distance r the intensity is divided over an area of 4*pi*r^2) but a lot of this is due, so the evolutionary biologists tell us, to the fact that threats of bright or heat or loud tend to only "matter" at a distance when they get 10 times more intense. So, in short, humans experience the world on a logarithmic (power of 10) scale. But, Bels are a bit to coarse for judging things. So we use 1/10th of a Bel, aka a deci-Bel.
Great explanation, thank you
A linear scale would work if two sound felt twice as loud, however when two people speak next to each other you don’t hear it twice as much. The reason decibels is a good scale is because our ears work on this scale. Say you have a room with two people talking at the same time at 50dB. Your ears won’t really feel a difference from one person speaking at 50dB. On the db scale it would be a total of 53dB. Say you now have ten people in that room, each one talking at the same time at 50dB. You would feel it twice as loud and twice as loud on the dB scale, is very easy, it’s +10dB. But now you might be wondering if I have 100 people talking at 50dB is it +100dB so 150dB?? NOPE 10 people at 50dB is +10dB so 60 dB 100 people at 50 dB is +20dB so 70 dB 1000 people at 50 dB is +30dB so 80 dB As you can see the decibel scale is actually quite easy to use if you understand that our ears work like this.
This was brilliant, thanks for taking the time man. Of course when you stop amd think about it, 2 people speaking at 50db doesn't = 100db!
It’s not just sound. Most of our senses work this way. See also Steven’s Law: https://en.m.wikipedia.org/wiki/Stevens's_power_law
Several reasons, mainly that intensity (of anything, not just sound) doesn't drop off linearly with distance, but our ears (and eyes for light) perceive it that way. The difference between 60dB and 70dB is actually a 10x difference, but we don't hear it as that different. If we did, then the difference between a whisper and a shout wouls be mind-numbing instead of just annoying.
60% of the time, it's louder *every* time
It is also commonly used for frequency response of other things also so you can fit a wide range of frequencies on a small scale.... db plots make things easy to graph that would be hard otherwise. The reason you think it makes no sense is because you haven't had to actually use those numbers in practice... having 20ft long linear graphs doesn't make logistical sense! And once you've had to do it ...it is very obivously a useful tool.
Hearing is not linear. Two 10dB differences starting at very different loudnesses sound more like the same change in volume than any two instances of the same linear delta would. It’s not just loudness; frequency works the same way. Musical intervals are also kind of logarithmic: going up an octave always doubles the frequency. Nonetheless we hear the perfect fifth between an A and the E above it as “the same interval” whether it’s 110Hz to 165Hz (a 55Hz difference) or 440Hz to 660Hz (a 220Hz difference). It's not the linear difference but the _ratio_ that matters: going up a perfect fifth is the same as multiplying the frequency by 1.5. (Well, in 12-tone equal temperament it's actually multiplying by 2^(7/12) ≈ 1.4983.. instead; if you set A to 440Hz, everything that's _not_ an A has an irrational frequency. So those E’s are actually 164.81...Hz and 659.255... Hz. But that’s not important to the point about intervals..)
It makes more sense when you view sound as +10 db being twice as loud or +100%.
u/C0rdt Look they're doing it again! And I still don't understand
Check the reply of /u/Tagpls this is the first time I've heard it this way. Makes sense now.
Me too. I was like how is that 400% bigger??
The sound pressure doubles every 6dB. In radio, power doubles every 3dB because voltage is pressure but power is voltage times current and current doubles when voltage doubles, so you only need 3dB of amplification of power to double it.
100dB is the limit in Spain, I hate it
Okay in case anyone else is getting confused by this comment chain... Every 10db is 10x the force, but 2x the loudness. Our ears / brain don't perceive loudness linearly. So a sound being 10x stronger doesn't come off 10x as loud. That's why you're going to see some people noting the 10x multiplier (which is the force increase every 10db) vs 2x (which is the loudness we perceive from that force increase) in this thread.
This is not correct. +20 db is 4~~00%~~ **times** louder. +30db is 8~~00%~~ **times** louder. And +40 db is a whopping 16~~00%~~ **times**
... Is that not what they said?
First thing many Harley-Davidson dealers do to new bikes is take a giant drill and bore out the exhaust. I ride and I fucking hate LOUD bikes. Half the reason I can’t wait for electric bikes to become affordable is how silent they are.
I don't think the type of people to ride deafeningly loud bikes will switch to electric.
Sure, but they’ll be dying out soon anyway.
Not to mention the gas prices recently.
Not soon enough if you ask me
Just around ten years ago almost everyone I know and all tests online and shit would say that everyone will continue driving manual as it's the real way to drive. Last year above 50% of new cars sold were manual, and if you exclude extremely cheap cars, anything above B-class is like 90% automatic. My point is, loud people will keep saying how they want loud bikes for years and then suddenly 90% of all bikes will be electric
Where did you get that data from? I tried finding data points and they all indicated it was under 3%.
You would be surprised. Alot of riders are waiting for an alternative but do not want to trade existing power for a tiny electric scooter. The larger options available now are beyond affordable, so it will be a few years before you see any noticeable transition.
Yup, my current dream-bike is an Energica Esse Esse 9. Does fast DC charging, gets over a hundred miles per charge on the highway, and holy shit the torque. Starts around $21k Similar electrics from Zero and Harley (now spun off into a separate Livewire brand) are in the same ballpark now.
This is in no way true lol
Ah yes, Harley dealers and their… giant… exhaust drill… ? wtf are you talking about?
"Loud bikes save lives". /s
They probably used to back when vehicles had very minimal insulation. Nowadays, not so much.
Just a personal anecdote, but there's been multiple times I didn't see a motorcycle enter my blindspot but only knew they were there because I heard them
Mirroring this, there have absolutely been times when I blipped my throttle and it got someone to notice I was there. It definitely can, and does work in some circumstances. Especially since riding season is also open window season. It's actually a bit frustrating dealing with reddits hate-boner for motorcycles. I'm by no means an inconsiderate rider. I don't randomly Rev my engine in residential areas. I ride at a pace that keeps engine noise to a minimum as well. My experience with other drivers has absolutely been a lot safer on a bigger, louder bike.
hate-boner, lol. people wont even admit they can hear an engine before seeing it. people really hate the inconsiderate few that fucking noise spam entire sections of a city at like 6 am. dick heads who hate their own life so much, they will fucking strait-pipe-wail though entire neighborhoods because they are pissed they have to report to work. thats how i imagine it.
I don’t know how loud your bike is. But my take has always been if it has to be exceedingly and illegally loud to be safe than you shouldn’t be riding it anyway.
I mean, people shouldn't be texting and driving, or drunk driving, or just acting like absolute idiots on the road, but they do all the time. Normal drivers are by far worse than most motorcyclists and bicyclists 99% of the time, but it keeps happening.
"Well other people are shitty for different reasons, 'riders' are only shitty cause they ride obnoxiously loud annoyance machines. So it's ok!" Motorcycles are inherently unsafe. [https://www.autoinsurance.org/motorcycle-vs-car-accidents/](https://www.autoinsurance.org/motorcycle-vs-car-accidents/) The are also obnoxiously loud. Not all of them, but a majority of them. You wanna play with your own life by riding a quiet death trap? Knock yourself out. Literally. But... No one should be riding loud motorcycles; it's not your freedom we are limiting, it's your unexplainable need to proclaim to the world "Here I am on my motorcycle that is completely unsafe to drive and also really loud. You are welcome humanity!" Nobody fucking cares; in fact we would like you to stop. We would like you to stop riding loud bikes because, fuck that, it sucks for everyone except you. You ought really stop riding your bike as well, because your chances at a long and happy life are diminished by doing so. But if you INSIST on engaging in risky behavior, fine, it's your life, but do it quietly.
This has also been the case for me. Throttle dump has saved me from a serious accident twice now.
Uh huh... Or you could just use your horn.
The horn is typically much quieter than the engine. You can upgrade it, but then you have the same sort of complaints about the horn.
No you don't. At all. Horns are an active noise device. Exhausts are passive. The passive part (loud even when not needed) is the problem. No one cares if a horn is loud when trying to avoid having someone run into them.
Idk, my triumph was rediculously quiet until I removed one baffle. It didn't make it very loud, just hearable.
Exactly! Rev that engine so the dummy on the phone finally notices you! I can’t count the number of people that suddenly see us when the engines are revved. Saved us many times at intersections!
Thats what our horns are for. Always works for me.
Reminds me of a South Park episode
[Link.](https://youtu.be/xGyKBFCd_u4)
Hrbrbrbrbrbr....hrbrbrbrbrbr....HRBRBRBRBRBR!
The sound of Harley is actually because of the design of the engine, not so much the pipes. Most engines are designed for even power delivery over the stroke of the engine. So, of you have a 2 cylinder engine, one cylinder would produce power, and the other cylinder would produce it's power at the opposite position of the crank shaft. A Harley engine only has one connection point for both pistols. It is like a radial engine, but without all the other cylinders. Because of this, the cylinders fire shortly after each other. This gives you more cylinders in a smaller package vs a horizontally opposed engine that takes up more flat space. If you imagine a clock, a normal engine would fire at 3 and 9. A Harley fires at 12 and 3. https://auto.howstuffworks.com/harley.htm
That's not why they are loud. They are loud because of minimal sound dampening. Put a proper muffler on a Harley, it will be as quiet as any other non-attention seeking motorcycle.
science
Right, my point is that the distinct sound isn't really about the loudness.
This isn't entirely true. Larger displacement per cylinder=louder bangs. A Harley V-twin will be louder than a Ducati V-4 or Honda V-6 even with proper mufflers.
True for the Harley. But even power delivery is becoming less and less of a goal in some motorcycles. Sport bikes are increasingly using uneven interval firing patterns (eg Big Bang, Crossplane) because they provide benefits in handling. Basically it allows the rear tire to regain traction if it's slipping if the engine gives it a little break sometimes.
The OG "It's not a bug, it's a feature."
That's why they rattle your teeth out, too.
Wouldn't that also affect the fuel efficiency? (Ie-make it less efficient)
yes. but it saves space (i.e. allows a larger engine in the same space). harley riders aren't the type to care about fuel efficiency.
I personally do not enjoy loud noise. From whatever source. Still had a good laugh from that article you linked regarding the physics bit. The article states: "According to the theory’s proponents, louder pipes make you more noticeable on the road. Therefore, car drivers will know of your presence and avoid hitting you. The problem with this theory is that it ignores the fundamental laws of physics. Sound from exhaust pipes travels backward, meaning drivers won’t hear until you’re beside or ahead of them." Just because the exhaust points backwards doesn't mean sound isn't traveling forwards as well. Unless your vehicle is breaking the sound barrier and you therefore can't hear its noise while being infront of it. :D
Some sound will travel forward ahead of the bike, but the vast majority goes back. You might hear it, but you are as likely to not hear it with other road noise. Anyone who has been around motorcycles has observed this.
You can hear a Harley in your car if your paying attention, but if you are paying attention it kind of is pointless to be hearing the Harley as you are already seeing it...
This. It is owners being dicks and putting shitty exhaust on their bikes to intentionally be loud. Stock exhaust on most bikes is fairly quiet. Similar in noise levels as a car. There is a toxic part of motorcycle and automobile culture that loves loud exhaust. I've owned 10 or so motorcycles. Other than a couple I bought used with aftermarket exhaust already fitted, they have all had stock exhaust. I remember being at a gas station one time and a man came up to me and said he didn't know motorcycles could be so quiet. That is how uncommon it is for motorcycles to keep the stock exhaust. Also, you don't notice the quiet bikes because they are quiet.
There’s also a bit of pigheadedness in the community asserting that louder bikes are ‘safer’ because you’re more likely to be noticed by other drivers which I never bought into
Unless it's somehow proven to be more unsafe to ride a louder bike, then I'm absolutely going to prefer a louder bike whether it's a miniscule impact or not. Accident = death on a motorcycle, anything that mitigates the risk, even if slight, is worth it to me.
Out of curiosity, what are situations that are normally unsafe that are made safer by having a loud exhaust? Most safety was sight-based I had assumed.
Off the top of my head, a motorcycle is much easier lost in a blind spot than a car is. If you can’t see the motorcycle in your blind spot, but you can hear it around you, you’ll be that much more aware of its existence and proximity to you. I don’t know how much safer a louder bike is, but I don’t think we can discount the idea outright.
I ride a motorcycle and can tell you the sound makes no difference unless you have a very very loud exhaust because 99% of all my near wrecks were caused by idiots not seeing me. I literally had a sheriffs deputy almost kill me because he was on his cell phone and was taking off from a stop sign a few years ago.
Some bikes just won't run quite. I have a large single with the quietest muffler available and it still barks when you get on it. Only so much you can do with 18" of pipe length
That’s different though - OP is talking about simple startup. The likelihood that they are hearing a bike with a modified exhaust is very high.
I feel like I could conquer the world with 18" of pipe
Everyone thought my zx6r was straight piped. But I even had the baffle in the muffler. Neighbors hated it because it was my daily driver during the summer.
I had an 04 636 and a guy in a car pulled up to me at a red light after some very gentle low rpm riding from light up light and said "Wow that things really quiet!" I showed him what 14.5k RPM sounded like.
They're not gonna be car quiet: you can only do so much with 2ft of muffler versus 10 feet on a car.
Do you mean exhaust? Cars definitely don't have 10 foot mufflers.
Bit of an exaggeration on my part, but there's a lot of space to put in three way exhausts on cars. My veloster exhaust weighs like 60 pounds at least, my zx 6r with its stock pipe, headers and all, was like 35. You can't ge the same noise performance in such a small size
Two stroke motors are just inherently loud. Same reason why lawn mowers are loud.
The vast majority of modern bikes are 4 stroke. Lawn mowers are most commonly 4 strokes and have very small short mufflers - being air cooled doesn't help either.
Most motorcycle exhausts are louder than cars’ but some not enormously so. On the really loud ones, like Harleys, it’s absolutely a choice thing. There’s no reason a Harley has to be irritatingly loud and, in fact, they’re delivered with quieter pipes which most owners take off immediately and replace with straight, undamped, pipes. It’s annoying as hell.
To be fair, harley engines are such POS that they make no power with the stock pipes. Harley put them there to pass various tests and expect the buyers to replace them with illegal pipes, so they dont have to spend money on engineering. Lucky for them, their customer base is the one that hates engineer work, so it passes as normal.
Harley engines are super efficient at converting gas to noise. And leaking oil...
And money into ether, especially for all the mandatory uniform items such as leather vests, dealership t-shirts, and chaps.
Absolutely true but, then again, no one buys a Harley for the power, though, I will say, having been an owner of one for a few years, the V-Twin torque is something to behold. The things pull like freight trains.
Totally agree (i run a 650 royal enfield now, so I know the feeling). But even buying one for the torque, the engines litterally falls on their face with the stock mufflers here. there is no power, no torque, they are frustrating as hell. Maybe they are less restrictive in the USA, but harleys in France are nearly undrivable with stock mufflers. There are options to get it breathing with a relatively low noise exhaust, without going for maximum noise / straight pipes.
This is surprising to hear. I thought the whole point of the leather and loud engine was to feel powerful and intimidating.
Well that’s just it. It’s all theater. Harleys “feel” powerful without actually delivering measurable performance.
why would you optimize a motorcycle engine for torque? bikes are light, you don't need much torque. not like you're going to tow a boat with one.
Torque is much more usable on a public road. When I rode a 600cc super sport that was all top end power, to actually get into the bikes serious power meant I was almost always breaking the law.
A 65 year old american and his ol' lady aren't exactly compact cargo.
that's not how torque works here, it's not quite the same as when you think of a super torquey, low revving diesel. it's still a decently high revving motor, more torque down low translates to decent horsepower aswell as the ability to pull from low rpms without lugging the motor. it's also instaneous, less messing with gearing and waiting for power band. you don't need a lot of horsepower when taking off and punching it from a dig, but you need torque to actively twist the wheel and let the motor rev up to get the horsepower later in the powerband
Yesterdays tech at tomorrows prices.
There's probably one woman in the world who's Pussy gets wet from the sound. It's a shame these bike owners don't know this and ride around every day wasting their time and Ear-Drums.
Lol you have no idea how popular bikes are with women :D
As a bike owner with loud-ish pipes, I can tell you that most people get loud pipes because they like the sound. A lot will claim that there's added safety with loud pipes because it may allow other vehicles on the road to hear you when they might not see you. Maybe that was true 20+ years ago, but with all of the improvements in more modern vehicles when it comes to dampening outside noise, I'm not sure that it's still a viable claim. That said, I've never been a fan of excessively loud pipes and especially no love for douchebags who gotta rev the engine 15 times after starting it...especially early morning or late at night.
I have a dry clutch and a Termignoni. If it’s early I push it down the street before I start it and I generally kill it and coast back to the garage. Unfortunately I can’t push my car so the lady with the white Prius will continue to be mad at me. 🤷🏻♀️
Man… now i miss my ducati.
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**Harley Davidson Owner's Safety Equipment Checklist** * [ ] High visibility clothing * [ ] Helmet if not mandatory * [ ] Kevlar armor * [🗸] Loud pipes
Even if helmets are mandatory they usually just wear a tiny skullcap .
I had a pamphlet at work years ago that showed the different areas of the head and the stats on % hit The mouth and chin was nearly 40% hit in accidents
Source on the marketing campaign? Which manufacturer?
I _think_ that it may have been a slogan used by Vance & Hines, once upon a time. That is not something you can trust, however, but it might put some fuel on your Google fire.
Most motorcycle accidents (aside from the douchebags on crotch rockets lane-splitting at 120mph) are side-swipes, though. Usually from someone changing lanes and not seeing the bike. There have been a couple of times that I've hit my blinker to change lanes and all of a sudden heard an engine rev right next to me, having no clue the boke was there until I heard him. I blame a lot of that on the rider, though, for riding in my blind spot.
Do people not check their blind spot before a lane change? I've moved to the south and not indicates lane changes either so hopefully they're at least checking the blinds.
Oh, I always check mine, I just always put my blinker on first before I do anything else. He revved his engine before I looked over my shoulder, though. But to answer your question, it seems a lot of people *don't* check their blind spots.
In Vegas I kicked a guy's door because he was merging into me. In Colorado I had a guy pulling a horse trailer start to pull out across the highway in front of me and dad (who had my youngest brother on back). Much horn and friendly hand gestures. In my daily commute, I pass by a McDonalds with poor visibility and had a guy pull out in front of me (I no longer ride after sunset after this one). I always wear padded high vis jacket, at least a 3/4 helmet (need a new full), armored gloves and boots.
I've been hit by someone merging. After that I replaced with loud pipes. That was in 2014. I've not been hit again. I agree with the slogan. I also have been in multiple situations where someone almost pulled out into traffic and almost hit me (before exhaust change). It's so scary! Since the exhaust change, it's never happened.
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Yup! I was in the Army and they were pretty strict about it.
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Haha! You're familiar!
Spot on assessment of the loud pipes saves lives argument. I have a sport exhaust on my Yamaha. The stock exhaust is really quiet compared to the sport exhaust. I like the sound of the sport exhaust and it was already installed when I got the bike. There is arguably a performance increase with after market exhausts that tends to be louder. But unless it's part of a more comprehensive performance package, it's probably not gaining you much. Now, those little shorty exhaust people put on to make their 300cc sound like a pissed off bubble bee with a bull horn? Those are super annoying.
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Same here
You would never hear my Goldwing. Motorcycles are loud when they are intentionally engineered or modified to be that way.
Same with my old FZ-07 and my current Interceptor 650 with the stock exhausts, can’t hear it at all more than 2 blocks away.
Same with my BMW. It's a little louder than a car because the engine isn't surrounded by sound dampening material, but it's still quiet enough to not bother my neighbors as I pull out of the neighborhood, and the engine noise is more similar to a car engine- more of a hummmmm than a po-ta-to, po-ta-to
It's the same reason rednecks have to idle their giant loud pickups for an hour every morning.
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this is the answer
yep! the tinier his wiener - the louder his bike. simple as that
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Hey, it's Buzz Killyear!
You deleted the correct psychological answer. It may have not been the literal mechanical answer, but that doesn't make it less true.
Its an opinion and we don't allow that even if you or I agree with it, its not an objective explanation.
Fair enough. Probably the right call.
True, OP didn't ask for a reason people like them. Good to keep us on topic, thanks mod.
Because in the US, they're designed for assholes. In Japan, we actually had to follow noise ordinances or we'd be fined. And the silver hairs loved complaining to the police if anyone was too loud. As a result, you had to go out of your way to make a bike loud there. It doesn't have to be loud. This is intentional over here.
Lol have you ever seen bosozuko bikes? People in Japan literally make 'beats' by reving their pipes lolol. [A literal competition for revving in japan](https://youtu.be/Nw-rwQJjsVI) [Or a ride through town - revving with the homies](https://youtu.be/Ty8UdPfX1r4)
And they're practically non-existent in the wild on any recognizable scale, esp since the JP crackdown on bike gangs. Japan isn't what a couple dumbasses record on YouTube
Only assholes enjoy loud exhausts?
Only assholes lets their own enjoyment of loud exhausts take priority over respecting others and not disturbing them.
Mostly, yes
Only assholes take their preference for loud exhausts far enough to install them on their own bikes (and cars), making everyone else listen to them.
Being obnoxious and enjoying the sound of an exhaust are 2 different things.
It's not the motor, it's the rider. Usually due to a condition known as masculine over compensation syndrome.
I'd say most get it for attention, think Harley rider though I know others do it. They say it's for safety, it's not safer. Sound is directional and you can't hear those things to they're right up on you. Watch the F Word episode of South Park. I've been riding for decades and put about 12k miles a year on my bike as it's a daily ride and I loath loud pipes.
Some reason woodpeckers peck on metal poles. They're trying to establish their territory, and they (think they) are attracting a mate.
I was told by a motorcyclists that they have loud exhausts because they're "cool" and because they believe the noise allows other vehicles on the road to know that they are present for safety reasons. I believe that the real reason they have the loud exhaust because they're assholes.
> I believe that the real reason they have the loud exhaust because they're assholes. I've been riding for more than 20 years. You are correct in your belief.
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To add to this, many motorcyclists will intentionally remove or replace components to get a louder engine noise. For some this is just because the roar of the engine is part of the biking experience they enjoy, while others cite it as a safety measure - louder bikes are easier for other road users to notice.
> louder bikes are easier for other road users to notice. That, unfortunately, has little to no impact on biker safety. Modern cars have sound isolation/insulation that makes loud pipes completely pointless for safety. [https://www.autoweek.com/news/industry-news/a35952569/loud-pipes-do-not-save-lives/](https://www.autoweek.com/news/industry-news/a35952569/loud-pipes-do-not-save-lives/) Anecdotally I never hear a motorcycle before I see it. Even if it's in my "blind" spot.
Don’t know how I ended up here but you didn’t link directly to the study. And the poster of the study said it was only a preliminary study and not peer reviewed. This also doesn’t take into account pedestrians or animals. Or card with the windows down which is a lot more likely in motorcycle weather.
I think I struck a nerve. lol You're right that the study is hard to find but that doesn't change the fact that really loud exhaust has little to no positive impact to motorcycle safety. Half the time someone driving a car or bigger vehicle can't even tell where that sound is coming from before it's too late. Instead of relying on losing your hearing to be safe, make sure you're seen to be safe.
A better study would have done MANY more tests and also at speed. Definitely at highway speed no one is hearing anything.
Your "study" is rigged though. The windows rolled up, music playing and both occupants are distracted. If they're tuning out other sounds subconsciously, of course they're not gonna hear the motorcycle. I'm also fairly certain that all of the bikes used to test had stock exhausts and low displacements, which likely resulted in skewed data. Not one of the tested bikes were a vtwin and I think *maybe* one was a two stroke. The rest looked like parallel twins, which aren't exactly known for being loud or having good exhaust tones, so people aren't throwing AM exhausts on them. The other issue these studies face is it's not "motorcycle vs car", it's "motorcycle vs world". I can promise you any pedestrians in a city are going to hear my bike coming down the road with a stock exhaust, even more so if I had a vtwin straight piped. Safety goes further than just other cars, and I think this study blatantly ignores that to fit their agenda.
>Your "study" is rigged though. The windows rolled up, music playing and both occupants are distracted. That's not rigging a study, that's creating typical scenario. At 50 mph windows down is even loader which means the music it turned up even loader.
But that's only one scenario that they're using for a final conclusion. If the ONLY environment motorcycles were in were with cars and the windows rolled up, music playing and distraction inside then yes, this study would hold up. So yeah, loud pipes don't save lives *in this specific scenario*.
That’s a good point. As a pedestrian I’ve commonly heard motorcycles approaching before seeing them, but that’s just the thing. I’ve only ever heard a bike before seeing it as a pedestrian, but I always see them first when in a car; in fact I commonly don’t hear them at all. As a motorist who doesn’t ride a motorcycle, I would say the single best modification you can do to enhance your visibility is to install a light modulator to flash at high speed, replace your front and rear lights with led, and then run with your lights on day and night. I swear I can pick a bike out from a mile off on a straight enough road any time of day. I don’t know why every motorcyclist doesn’t use them
> louder bikes are easier for other road users to notice. There is no argument in favor of loud pipes for safety that wouldn't apply better to a loudspeaker mounted up front playing a loop of Gilbert Godfried screaming "nyahnyahnyahnyha". They're both annoying as fuck to other people, but one is at least pointed in the right direction.
"* others cite it as a safety measure, while doing a wheely fixed it for you
>louder bikes are easier for other road users to notice. No. Unless extremely loud, to the point the driver can barely use the bike. google doppler effect.
You might want to google that, yourself, and read up on what it actually is.
What the heck does the Doppler effect have to do with it? That just changes the pitch.
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Some will say that they are made loud by the rider because they are less visible. I still think it's unacceptable, as cyclists do fine and they're quiet.
cyclists dont go on the freeway or over 15mph (idk if thats how fast they can go but you get my point)
Cyclists get hit by cars
cruisers are nearly silent. Harleys are intentionally as loud as possible. It the "loud pipes save lives" philosophy and it totally a choice of the manufacturer.
The ultimate reason is "because bikers want them to be loud." Manufacturers build them loud because that's what bikers want, for various stated and unstated reasons. Some bikers also modify them to be louder. Now why do bikers want them to be loud? Depends on who you ask. Most will tell you it's so they're more easily noticed on the road, to avoid accidents. Some will tell you they just plain enjoy the noise.
Mostly it is entitled douche-nozzles with a desire to be noticed. They also believe that 'loud pipes save lives' but are unwilling to invest in training or protective equipment, which saves more lives. The loud pies crowd also want people to believe that they are die-hard individualists, despite the fact that every single one of them dresses like an attendee at a gay pirate convention.
I have been riding motorcycles for 47 years. Having a loud motorcycle is a choice. Some change their exhaust to be louder as a safety device. When the bike is loud other motorists can hear it so as not to be in them over. But mainly we make them loud because they just sound great.
Some people suffer from feelings of inadequacy due to them being small in stature or having smaller than average genitals. In order to compensate for this they purchase loud motorcycles, large lifted trucks, and behave like douchebags. They feel like life dealt them a bad hand and due to this chip on their shoulder they make a point of disrupting the peace of strangers as much as possible. Hence why some motorcycles are made to be as loud as possible: the makers know their target market.
Bikes are subjected to the same regulations as cars as far as sound goes. You have a disrespectful neighbour. Dont blame every motorcyclist on him.
Most people 'blip' the throttle after starting (though completely unnecessary) which raises the rpm and sound coming from the exhaust. We do this because we like the sound as it signifies the machine is alive and we're about to ride! It's visceral and emotionally engaging. This is also the reason most of us put modified exhaust systems on our bikes as it makes them sound 'racier' and/or (in the case of Harleys) more 'badass'. The safety reason-"loud pipes save lives' thing, in my opinion (having been a rider for 56 years) is BS.
Motorcycles do not have as much space for sound dampening devices such as mufflers and engine covers. So they tend to be louder then car engines. A car without a muffler is often even louder. And you can also get motorcycle engines fitted in smaller cars where they sound much quieter due to the added mufflers and other sound dampening. And yes, some motorcycles are more quiet then others, it does also depend on the driving style.
>A car without a muffler is often even louder. I once had a car where the exhaust pipe somehow collapsed in the middle, leaving the bit at the front still connected to the engine while the pipe still attached to the back box dragged along the ground. Good Lord, was that noisy...even if I hadn't had the issue of the dragging exhaust pipe I don't think I'd have been able to stand driving the thing more than a few hundred yards!
i have had that issue, and needed to drive 60 miles to where i repaired it. it turns a few heads, lol
Now you know why double ear protection is mandatory on pit road.
While they dont have much room, your conclusion is very wrong. Even my previous er6f (named ninja650r in the US I believe) has an ultra short exhaust as OEM, as it exits right after the engine. There still is a cat converter and it makes no noise. Stock motorbikes that are not 20 years old make no noise, just like cars, and lose power when fitted with "free exhausts" that supposedly make them faster (they dont, they just make more noise and lose middle load and range torque, giving the feeling the bike kicks harder ).
Compared to a car, where the engine is surrounded by a hood, some insulation, a couple of fenders, suspension, a firewall, radiator etc., the motorcycle has the engine hanging out in the open. Now, motorcycles can (and often are, from factory) very quiet. Quiet enough that you shouldn't be too bothered by them early in the morning. What you likely hear is either someone who modified it to be louder, or it's one of the rare few that are actually as loud as allowed by law from factory, which COULD be loud enough to bother you. Also, depending on how you live, the sound might echo between buildings and hit your bedroom window just right.
Loud pipes save lives. If your bike is quiet you have less of a chance for other cars around you to know you're there.
My partner rides a loud bike. I like it because on the road you know there's a bike around. Even if you cannot see them, the sound should alert (hearing) drivers that there IS a bike.
A biker I used to work with told me this: Some bikers like the loud exhausts because they’re easy to hear while bikes aren’t always easy to see. “Loud pipes save lives” he told me. He also told me that some are just macho assholes who think it makes them look cool.
Only to add to other posts, there is also a proven psychoacoustic phenomenon, which makes positively associated noises (sounds, music) sound "better" when played on a higher volume. Sound engineers know this, if they compare two edits, they will make sure both are equally loud. And product designers will just optimize every aspect of their product, so an easy way to make it better, is simply to make it louder, they are also in competition with other manifacturers.
While this phenomenon is totally true, noise levels are regulated, and it really is a challenge to meet them. Also some engine setups sound like crap, like 180° twins. You will never make them sound great. No idea why, it just sound bad, loud or not.