[Toontje]

https://www.cartoq.com/police-fine-3000-royal-enfield-owners/

[axman88]

I laughed at the picture of the cop with the decibel meter 1/2" from the tailpipe.  Doesn't he know that if he bangs it against the muffler, he can get ANY machine to register excessive noise levels?  It doesn't even need to be running.

My state's laws says:
     Mufflers are required and must be in good working condition and not emit sounds higher than 85 decibels when going over 35 miles per hour.
     Mufflers can’t be altered to produce sounds louder than the original manufacturer equipment.

Hah!  I can't think of many HD machines that would pass those criteria.

If local law enforcement decided to jump on the gravy train, like they are in India, I bet they wouldn't enforce it via a squad of four foot cops and a $14 fine.  They would put microphones on the speed cameras and use an AI algorithm.  They would send you, through the mail, your speeding ticket, your noise violation, your frame height modification violation, and cite you for not having current tags on your dog, all at the same time.

[Bilgemaster]

Well, if they're also commencing to lean on manufacturers and installers in India, or at least parts of it as the article claims they might, then that might be good for us elsewhere, as those vendors try to shed their non-stock stock abroad for whatever they can get for it such as via eBay. So, don't be shy about using that "contact seller" or "make offer" feature where available, link to that article, and toss 'em a low-ball offer. They're already hitting you up for about twice what they're asking for the same gear in their home market. (And a new 2021 Interceptor costs less than $3,700 there).

Whatever may happen in future, at present, and even with its forthcoming updates (see: https://law.lis.virginia.gov/vacode/title46.2/chapter10/section46.2-1049/#:~:text=No%20person%20shall%20drive%20and,for%20motor%20vehicles%2C%20such%20exhaust), the vehicle exhaust noise regulations here in my home state of Virginia seem "practically unenforceable in the field" for most any intact-seeming exhaust system--at most just another vague hue for a cop's Pallet of Officious Annoyance, like if they were to write you up for a dirty license plate or a burnt out or "too dim" bulb lighting it or worn wiper blades.

I understand that the situation is very different in other states, notably California. There was a recent thread and lots of stories about that state going after and ruinously fining some aftermarket suppliers per infraction to the point where virtually every exhaust-related ad one now sees includes "Will not ship to California".

For a very basic state-by-state rundown on applicable exhaust noise laws, see: https://www.semasan.com/resources/exhaust-noise-laws-state.

[Richard230]

A couple of years ago, California fined Revzilla $1.5 million for selling mufflers to California residents that were not approved by the state regulators. The only mufflers and exhaust systems that are approved are stock equipment that is installed by the factory when the bike is sold, or one that is specifically approved by the motorcycle manufacturer as an accessory that meets State emission and noise regulations. Revzilla paid the fine and now will not sell aftermarket exhausts to residents of CA. (Now they need to be smuggled into the state.  ) The reason Revzilla didn't argue about the fine is because it could have gone up to a maximum of $150 million.    So the Indian cops are a bunch of pikers when it comes to collecting noise fines. 

Interestingly, I have never heard of motorcycle or car loud exhausts being enforced by the cops. You should hear the noise as both motorcycles and sports cars drive by Alice's Restaurant on Sunday morning. You can't even hear yourself think. But the cops don't bat an eye.  Apparently giving out speeding tickets is a lot easier than chasing after vehicles making a lot of noise.

[axman88]

Interestingly, I have never heard of motorcycle or car loud exhausts being enforced by the cops.

The  California cops probably looked over what is involved in making a test "in accordance with Society of Automotive Engineers Standard J1169 May 1998", and decided they are too cool for that nerd stuff:  https://strong-clan.smugmug.com/photos/14117811-O.jpg

As a nerd, I'd be taking some discrete cell phone pictures, and presenting my evidence to the judge showing why the test results are clearly invalid, because the 2nd microphone position was 15 inches, not the prescribed 0.5 meter, and whoever parked the bike had placed it too close to the guard rail, violating the required 3m of clear space.  Only Robocop or Inspector Gadget can chasten Engineer Man!

[Morgan65]

Hah!  I can't think of many HD machines that would pass those criteria.

I also own and ride three Harley Davidson bikes and I’m a member of Harley Owners Group or HOG. Believe it or not, I see/hear more HD look alike/clone bikes with stupid loud pipes then HD bikes. I see/hear more loud pipes in California than any other state. This I chock it up to lane splitting. “Loud pipes save lives” as they say.  If you have loud pipes the cars can hear you coming up behind them and they do move over to let you pass. To bad lane splitting is not legal in all of the fifty states.

[zimmemr]

Connecticut has some odd MVD rules, among them no state inspection of any kind for motorcycles, which essentially means that anything goes. However there is a clause in the code that states the motorcycle has to have all of it's DOT required equipment intact, for the year it was built. It doesn't have to be OEM, if your motorcycle was sold in a year when turn signals were required, that it has to have signals of some kind.

As far as exhausts go they don't bust cars or bikes for loud exhausts as they have no way of accurately testing anything to DOT standards, a simple sound meter won't get through the courts here.

But if you're stopped for some other infraction and you give them any attitude what they will do is inspect your pipe to see if it has a DOT sticker certifying it for street use. If your bike was built after DOT muffler stamps were instituted, and the mufflers on your bike don't have that stamp, it doesn't matter if they're quiet as a mouse, you're getting fined. If it does carry a stamp, it doesn't matter how loud they are, you're going to skate.
It's weird wrinkle but actually works fairly well.

[Richard230]

Connecticut has some odd MVD rules, among them no state inspection of any kind for motorcycles, which essentially means that anything goes. However there is a clause in the code that states the motorcycle has to have all of it's DOT required equipment intact, for the year it was built. It doesn't have to be OEM, if your motorcycle was sold in a year when turn signals were required, that it has to have signals of some kind.

As far as exhausts go they don't bust cars or bikes for loud exhausts as they have no way of accurately testing anything to DOT standards, a simple sound meter won't get through the courts here.

But if you're stopped for some other infraction and you give them any attitude what they will do is inspect your pipe to see if it has a DOT sticker certifying it for street use. If your bike was built after DOT muffler stamps were instituted, and the mufflers on your bike don't have that stamp, it doesn't matter if they're quiet as a mouse, you're getting fined. If it does carry a stamp, it doesn't matter how loud they are, you're going to skate.
It's weird wrinkle but actually works fairly well.

That is pretty much the same situation as in California.

[zimmemr]

That is pretty much the same situation as in California.

I didn't know that, I always thought they were stricter. NY state can be a pain in the ass. A few years back, they set up a blockade on the Taconic Parkway and pulled over every single bike that went past. They checked the pipes for stamps, and went over the bikes for equipment violations. They wrote something like 300 tickets, and never inspected a single car. There was some blow-back about it, but I don't know the outcome.

[Bilgemaster]

There's a video of a "Motorcycle Checkpoint" in the city at https://youtu.be/1xT3dvYh72g. It looks to me like they have a bunch of trainees out there breaking in their new uniforms in a low risk exercise just hassling passersby and generally wasting everyone's time. Asked politely to cite the ordinance one of them claims prohibits helmet cameras like the rider is wearing, after much poking of handheld devices none of the nine or so in attendance is able to do so.

The comments have since been turned off, so the outrage must have grown white hot. Obviously, I have issues with motorcycles being so specifically targeted for stops by law enforcement simply because they're motorcycles just to give blue newbies some street time. Let 'em go count the squirrels in Central Park or something instead of just annoying the passing citizenry.

[Richard230]

For some odd reason the People's Republic of Kalifornia, doesn't seem to hassle motorcycles much. There are no emission checks, no chassis safety checks, no enforcement of noise and muffler laws (other than going after retailer that sells them), no checking of lighting equipment and little attention paid to expired license tags. We have a ton of laws, but all the cops seem interested in is giving out speeding tickets.     I have never understood the concept behind enacting laws and then not enforcing them. I guess it gives our legislators a warm fuzzy feeling when their laws get passed, put on the books - and then forgotten. 

[zimmemr]

For some odd reason the People's Republic of Kalifornia, doesn't seem to hassle motorcycles much. There are no emission checks, no chassis safety checks, no enforcement of noise and muffler laws (other than going after retailer that sells them), no checking of lighting equipment and little attention paid to expired license tags. We have a ton of laws, but all the cops seem interested in is giving out speeding tickets.     I have never understood the concept behind enacting laws and then not enforcing them. I guess it gives our legislators a warm fuzzy feeling when their laws get passed, put on the books - and then forgotten. 

I think you nailed it. Once the legislators pass a law they figure their work is done, whether it gets enforced or not is another story.

[Karl Fenn]

And l guess the judges would find you guilty, saying sorry we need the revenue, every so often they have these purges when their budgets go in to the red, fairly typical behaviour.

[tartopum]

To say that a motorist hears a motorcycle with a noisy exhaust coming behind him and that this avoids accidents is a myth created by HD owners. (No study proves that). The only time a motorist actually hears a loud motorcycle exhaust is after passing the automobile.

Moreover, paramedics and police have the same problem because motorists (unless they are stationary) hear very little the sound of the siren because the movement of the air carries the sound towards the rear of the vehicle. (that there have been studies on).

So your loud muffler that already pushes the sound backwards pushes it even harder when the motorcycle is in motion ....!

[Karl Fenn]

Well l think local government is forever expanding, its got to the point where it is a Masonic club, no outsiders allowed with selection committees and such like picking the fodder, as their greed leads them to larger pensions, there will be more and more rediculous laws to scam money and pay for it, after all everyone would like a pension they have paid nothing towards.

[zimmemr]

To say that a motorist hears a motorcycle with a noisy exhaust coming behind him and that this avoids accidents is a myth created by HD owners. (No study proves that). The only time a motorist actually hears a loud motorcycle exhaust is after passing the automobile.

Moreover, paramedics and police have the same problem because motorists (unless they are stationary) hear very little the sound of the siren because the movement of the air carries the sound towards the rear of the vehicle. (that there have been studies on).

So your loud muffler that already pushes the sound backwards pushes it even harder when the motorcycle is in motion ....!

I don't think that myth can be attributed solely to HD rider's but other than that I've got no argument.

[viczena]

Maybe there is no study to prove that load pipes save lives.

What I know is the effect of a nearly noiseless group of  Racing bikes which come from behind and pass you with high speed. And you dont see (hear) it comming until they are ahead of you. Without warning.

Even more dangerous if you drive in a group.

[zimmemr]

Maybe there is no study to prove that load pipes save lives.

What I know is the effect of a nearly noiseless group of  Racing bikes which come from behind and pass you with high speed. And you dont see (hear) it comming until they are ahead of you. Without warning.

Even more dangerous if you drive in a group.

Very true, I've been caught unaware several times by sport bike hot shoes that snuck up on me. Some of then had aftermarket pipes some didn't but none of them made their presence known until they were right alongside of me. 

[fressko]

I remember many years ago in my former communist country bikes were a prized treasure, few and far between AND a car replacement. There was never any checkup for sound, we were al passing the MOT equivalent with all kinds of home made open pipes... Things have changed and now you might not pass with any aftermarket. Soon probably you WILL NOT pass with anything other than bone stock. Probably India is moving the same way. The longbottle might soon be a rebel's relic and an expensive proposition. Also, as a motorcyclist, I am pretty used to being harassed by police, is what they do. Pretty much like dogs chasing motorcycles, conditioned by some of our young fellow riders which go to 12000 rpm at midnight with baffles out.

[Liberty Blacksmith]

The link to state laws cites a Wyoming state statute but I can vouch it absolutely is not enforced. Vehicles with defective mufflers are never stopped and the county deputy sheriffs have told me no such law exists.
There's a difference between obnoxiously loud pipes, ie HD riders, and motorcycles which are too quiet. My BMW was in the latter category so I never tarried in passing someone. The pipes I just put on the Interceptor are fine with the baffles in place.
Looks like the pigs in India are running hog wild....

[Richard230]

The link to state laws cites a Wyoming state statute but I can vouch it absolutely is not enforced. Vehicles with defective mufflers are never stopped and the county deputy sheriffs have told me no such law exists.
There's a difference between obnoxiously loud pipes, ie HD riders, and motorcycles which are too quiet. My BMW was in the latter category so I never tarried in passing someone. The pipes I just put on the Interceptor are fine with the baffles in place.
Looks like the pigs in India are running hog wild....

My observation from the Alice's Restaurant area on an early Sunday morning is that Japanese "tuner" and expensive sports cars are now making more noise than the H-D crowd. Even they wince when those cars go by. 

Needless to say, neither the CHP nor the county sheriff seem to want to enforce California's draconian car muffler laws. Just one more law of many which are passed by the legislature that many people don't pay any attention to.   

[axman88]

Needless to say, neither the CHP nor the county sheriff seem to want to enforce California's draconian car muffler laws. Just one more law of many which are passed by the legislature that many people don't pay any attention to.   

You might be interested in this article that includes a response from a CHP officer as to why they don't enforce the noise laws:

https://patch.com/california/berkeley/ask-a-cop-why-deafeningly-loud-motorcycles-not-cited

Meanwhile, here in Chicago, we've seen increasingly large and increasingly unruly groups of motorcyclists, which has definitely gotten the attention of the locals who witness the events.  I'm talking hundreds of bikes, riding en-masse in street traffic without license plates.  Check out the video starting at about 1:38 to get an idea of what this looks like:
https://news.wttw.com/2021/08/02/chicago-residents-fed-noisy-caravans-motorcycles

I've seen multiple wheelie riders side by side, on a busy Chicago street, with pedestrians (myself included) and al fresco diners just 15 feet from the line of travel.

[Richard230]

You might be interested in this article that includes a response from a CHP officer as to why they don't enforce the noise laws:

https://patch.com/california/berkeley/ask-a-cop-why-deafeningly-loud-motorcycles-not-cited

Meanwhile, here in Chicago, we've seen increasingly large and increasingly unruly groups of motorcyclists, which has definitely gotten the attention of the locals who witness the events.  I'm talking hundreds of bikes, riding en-masse in street traffic without license plates.  Check out the video starting at about 1:38 to get an idea of what this looks like:
https://news.wttw.com/2021/08/02/chicago-residents-fed-noisy-caravans-motorcycles

I've seen multiple wheelie riders side by side, on a busy Chicago street, with pedestrians (myself included) and al fresco diners just 15 feet from the line of travel.

Well it is true that a "fix-it" ticket doesn't generate any revenue for the People's Republic of Kalifornia, whereas a speeding ticket brings in big bucks - starting at around $500 and going up from there.

Those crazy riders, mostly on unregistered dirt bikes and quads have been doing the same thing around here for the past several years. 

[GlennF]

So your loud muffler that already pushes the sound backwards pushes it even harder when the motorcycle is in motion ....!

So we should all retro fit forward facing mufflers for safety ? 

I suppose one solution would be to fit our Enfields with the ubiquitous PT6 which, being a multistage axial compressor reverse flow design, would do the job nicely while providing a nice power boost of up to 1900 or so Shaft HP depending on the exact variant fitted.

[AzCal Retred]

Looks like the 150 Kg, 550 HP PT6A-21 might be just the ticket, but the stock Bullet 4 gallon fuel tank seem unlikely to last more than 4 - 8 minutes.   The frame & swing arm may need strengthening as well. Not sure how the spoked wheels would hold up, but a set of 4.00 x 19 Duro HF308s would likely survive the additional weight, at least until you blipped the throttle. A test pilot may be tough to find. In the words of my old shop foreman when faced with questionable requests from Management - "Well, now we needs us a stoopid guy".

https://en.wikipedia.org/wiki/Pratt_%26_Whitney_Canada_PT6
" The Pratt & Whitney Canada PT6 is a turboprop aircraft engine produced by Pratt & Whitney Canada. Its design was started in 1958, it first ran in February 1960, first flew on 30 May 1961, entered service in 1964 and has been continuously updated since. It consists of two basic sections: a gas generator with accessory gearbox and a free power turbine with reduction gearbox, and is often seemingly mounted backwards in an aircraft in so far as the intake is at the rear and the exhaust at the front. Many variants of the PT6 have been produced, not only as turboprops but also as turboshaft engines for helicopters, land vehicles, hovercraft, and boats; as auxiliary power units; and for industrial uses. By November 2015, 51,000 had been produced, had logged 400 million flight hours from 1963 to 2016. It is known for its reliability with an in-flight shutdown rate of 1 per 651,126 hours in 2016. The PT6A covers the power range between 580 and 1,940 shp (430 and 1,450 kW) while the PT6B/C are turboshaft variants for helicopters. "

[Karl Childers]

The older I get the quieter I like my motorcycles....to a point. I like a nice exhaust note and to be able to hear what the motors is doing. Where I live noise levels are not enforced on anything, cars trucks or motorcycles. When I bought my most recent Harley it was whisper quiet and not at all what I wanted sound wise so I got some Vance and Hines slip on mufflers that turned out to be ear splitting, fortunately they offered 3 different baffle options and for me and their quiet baffle turned out to be just right, a nice low rumble at idle and not loud at all unless you go hard on the throttle but still nothing like the straight pipes a lot of guys run. Same for my Enfield's new exhaust, H's offered a quiet baffle for what otherwise amounts to a competition muffler that quiets it down to a nice acceptable exhaust note, not obnoxiously loud but not silent either. A big part of motorcycles for me is being out in the wind, feeling the bike under me and hearing the engine, it's an experience like no other.

 

[Morgan65]

I just got back from a ride to east TX and AR.  Because of the weather I took the southern route riding there and back. I took I5 all the way through Cal. Then took I-10 and some I-210 all the way across southern Cal.  I have to tell you loud pipes really help when you are lane splitting. People hear you coming up from behind and they move over to let you through. So yes in this case loud pipes do saves lives.

I have never been pulled over for loud pipes in 50 years of street riding. Besides my Himmy all my REs have louder pipes then any of my Harleys. Before you ask, no I don’t run strait pipes or abnocheous loud pipes ether. I do however like to hear the motor. Also I see/hear more Honda, Kawa, Suzuki, and Yamaha Harley clones with abnocheous loud pipes then I do HDs.

[Richard230]

I just got back from a ride to east TX and AR.  Because of the weather I took the southern route riding there and back. I took I5 all the way through Cal. Then took I-10 and some I-210 all the way across southern Cal.  I have to tell you loud pipes really help when you are lane splitting. People hear you coming up from behind and they move over to let you through. So yes in this case loud pipes do saves lives.

I have never been pulled over for loud pipes in 50 years of street riding. Besides my Himmy all my REs have louder pipes then any of my Harleys. Before you ask, no I don’t run strait pipes or abnocheous loud pipes ether. I do however like to hear the motor. Also I see/hear more Honda, Kawa, Suzuki, and Yamaha Harley clones with abnocheous loud pipes then I do HDs.

Around the SF Bay Area, lately it seems as though many car owners seem to also feel that loud pipes also save lives. This year many young men driving "tuner" and semi-sports cars have been using mufflers that are really loud and have an irritating pitch that sound like a glass-pack with the glass blown out. These vehicles have supplanted Harleys as environmental noise makers. Now there are more H-D riders playing loud music on their boom boxes than rattling the neighborhood with their loud pipes. Given enough time stereotypes do change. 

[Arschloch]

Around the SF Bay Area, lately it seems as though many car owners seem to also feel that loud pipes also save lives. This year many young men driving "tuner" and semi-sports cars have been using mufflers that are really loud and have an irritating pitch that sound like a glass-pack with the glass blown out. These vehicles have supplanted Harleys as environmental noise makers. Now there are more H-D riders playing loud music on their boom boxes than rattling the neighborhood with their loud pipes. Given enough time stereotypes do change. 

One thing I´ve noticed with Swedish HD riders, they have the urgent need to do everyhing better you do. So if your RE pops a little bit a HD guy will  come allong and pop little more. 

[axman88]

It appears that the boys in khaki in Hyderabad have taken this to the next level.

https://www.cartoq.com/hyderabad-police-destroy-royal-enfield-bullet-aftermarket-exhausts/

The article states that "two-wheelers can permit a max sound of 80 decibels", but doesn't state the distance at which the measurement is taken.  Because sound level follows the inverse square law, intensity drops off rapidly with distance.

Current US noise standards are also in the 80s, specifically, 84 dB when measured at 50 feet in the USA.  This translates to about 115 dB in the saddle, which is a level that can do hearing damage in a matter of minutes, and considerably more at the tailpipe.

When the original reports of fines in India came out, I recall seeing photos of a policeman holding a dB meter within an inch or so of a tail pipe, which is going to result in a very high measurement.

[viczena]

To say that a motorist hears a motorcycle with a noisy exhaust coming behind him and that this avoids accidents is a myth created by HD owners. (No study proves that). The only time a motorist actually hears a loud motorcycle exhaust is after passing the automobile.



So your loud muffler that already pushes the sound backwards pushes it even harder when the motorcycle is in motion ....!

And there is no study that proves the contrary. So we are back to have to think for ourselves. And even a baby knows, that loud sound catches attention.

[viczena]

Current US noise standards are also in the 80s, specifically, 84 dB when measured at 50 feet in the USA.  This translates to about 115 dB in the saddle, which is a level that can do hearing damage in a matter of minutes, and considerably more at the tailpipe.

The sound of the wind in the helmet is still louder. So even if you drive an electric bike, you are prone to deafness (after your theory)? Now what? Forbid helmets? Or wind? Driving bikes at all?

[AzCal Retred]

These are your friend...Deci Damp 2 Disposable Ear Plugs, $0.65
Nobody has "tough ears"...

[viczena]

So no need for silent exhaust anymore.

[AzCal Retred]

My cheap full-face has a lot of wind noise, even at 45-55 MPH. The mighty ES350 even with a Hitchcock's Gold Star "straight pipe" isn't too offensive, ear plugs work passably well. An upgraded helmet might be a better solution. Intake drone seems to be about as loud as the pipe.

The only drawback to loud pipes is instigating competition from other testosterone-infused warriors. We had an Arizona Gold Wing rider that carried a chromed service 45 ACP holstered on the steering stem for when the local prats wanted to "play", apparently attracted by the mere presence of a 2-wheeled but whisper quiet road burner. More than one had a sudden "come to Jesus" epiphany when our boy reached up and patted the piece the local Yobbos has overlooked. Deliberately attracting attention is a two edged sword, best to actually have a sword if that's your game.

[axman88]

The sound of the wind in the helmet is still louder. So even if you drive an electric bike, you are prone to deafness (after your theory)? Now what? Forbid helmets? Or wind? Driving bikes at all?

No.  You are missing every point.

Perceived noise, at the rider / driver's ear, is a combination of engine, tire and air stream noise.  Air stream noise is not transmitted to listeners in the environment, because it's a skin effect, but is only perceived by the driver / rider.

Helmets, like any barrier, will attenuate sound levels at the position of the ear.  Helmets create their own skin effect air stream noise.

The point I was making is that the USA mandated max noise level, of 84dB at 50 feet, if it was coming solely from exhaust noise, would translate to the much higher level of 115 dB at 4 feet from the exhaust outlet, where the rider's ear is.

Noise levels from road noise at highway speeds will be well below this, probably less than 105db.  Noise levels in the cabin of a car at highway speeds have been measured at around 70 -80dB.  Here's a bunch of measurements of different cars:  https://alexonautos.com/cabin-noise/    A typical car reduces noise levels with the windows closed by about 6 dB vs with the windows open. 

there is no study that proves the contrary. So we are back to have to think for ourselves. And even a baby knows, that loud sound catches attention.

The study from Association for the Development of Motorcycling in Romania, in conjunction with the Department of Road Vehicles at the Polytechnic University of Bucharest does specifically conclude that motorists in enclosed cars will not hear a motorcycle overtaking from behind, until the motorcycle is within 10 meters.  Only preliminary results of this study have been published to date.

Noise abatement laws are seeking to protect others from an individual vehicles excessive noise, not to protect the rider / driver from his own foolishness.  I think that besides subjecting a rider to legal prosecution, and possibly assault from other, very annoyed, motorists, constant loud noise has been shown to dull the senses, have negative health effects, and it renders the rider effectively deaf while underway.

I don't expect to convince you.  As you say, even a baby knows what it knows.  I am certainly willing to agree that "Loud Pipes scare small children" 

[viczena]

I can assure you, that every car driver will hear me, if I want to . Even the romanian ones.

And scaring small children is not the worst scenario, so that they dont decide to jump on the road in front of your bike. Live saved by loud pipes.

[Morgan65]

And there is no study that proves the contrary. So we are back to have to think for ourselves. And even a baby knows, that loud sound catches attention.

+1
I also have three Harleys and two Guzzis with loud pipes.
When l’m lane splitting in California the cars move over easily 16 to 20 inches on ether side two to three cars ahead of you, when in very slow traffic, that is if they can hear you coming!

[Richard230]

My observation is that many motorists are spending more time looking in their rear view mirrors while driving in heavy stop-and-go traffic than they used to do and will move over when they see a motorcycle rider behind them in the adjacent lane. And it is my opinion that they do so not because of loud noise, but because they are worried about damage to their expensive rear view mirrors and don't want them to be knocked off or damaged by the motorcyclist's mirror hitting them. I say this because I do encounter cars moving over for me when I am riding my quiet Zero electric motorcycle.

[Morgan65]

LOL! I’ve done lane splitting with a quiet 1800 Goldwing and I can tell you loud pipes do make a difference. Believe it or not, I’ve been there done that. Also I’ve riding for over five decades and one thing I’ve learned, everyone has a opinion. Right or wrong. 

[Carl Fenn]

They certainly make a difference to pedestrians all these electric bikes and cars are deadly silent.

[AzCal Retred]

Well, in the words of a long time contributor elsewhere -
" Well you see no one pays any attention until it effects them certainly will over the next ten years, .... the problem is our genetically defective police won’t let progress take it course, they have none sensible laws and want to corporate exploit everyone ....  "
Weeding out the inattentive and biologically defective seems to be the intent here, so you can hardly fault silent EV's (or well designed 2-wheeled Japanese infernal combustion flat 6 motorcycles either ) for furthering "progress", right? That statement clearly espouses "laissez-faire survivalism", so logically ultra quiet, powerful machinery fits right into that scheme. Just remember to look twice before stepping off the curb, eh? 

[Carl Fenn]

Well it always makes me laugh when you see police lecturing riders on the road side about how they have to pay to keep their private vehicles on the road, what they should say is we have to spend some of our nicked money we stole from mugs like you.