https://www.nbcnews.com/id/wbna43154773

> "What we managed to show is the combination of the crosswind and the temperature gradient can cause sound that's going to go vertically (to) get refracted back down," he said. "The sound was literally bent back downwards."

> The effect often happens at dawn and dusk because sound bends from hotter air into cooler air. During the day, the ground is hotter than the air above it so sound bends vertically upward.

> "Its only when the sun stops falling on the ground that the ground cools down. Then the air gets hotter above," he said. "That's when sound can bend towards the ground and become trapped."

We don't need the windows open to hear the cars and such around here (and they're modern windows). We're near a freeway, but it's not the only culprit. The freeway is either silent or quite noisy depending on ambient weather conditions.

But when the cars open up, it sounds like a racetrack. We can hear them accelerating up the on ramp, up shifting as they go, and even when they hit the flyover to the other freeway.

The ratio of motorcycles to cars is actually quite low. Most of the offenders are the V8 pony cars.

I sure am glad for the riding classes I've taken, however, which probably do a lot more good than obnoxious exhaust systems.

Actually, is there a single thing that insurance gives you a discount for?

Like, I’m with GEICO and as far as I can tell, it’s only age of license without accident or ticket that counts.

Either every factor is a wash or insurance companies are keeping the spread as profit on their side or they have no means of enforcing.

Like, do you install a Termignoni and then call your insurance agent? “Hi, I got louder exhaust pipes installed. Also, I’ve decided to wear a nicer helmet. Also, I now keep my bike inside a garage. Just wanted to call about the discount”

ABS, having taken a Motorcycle Safety Foundation riding course (in the U. S.), and yes, for storing it in a garage. All of those are items for which Progressive gives a discount.

Less of this, please

As a corollary anecdote, I've seen (and heard), on several occasions, the rev bombing riders revving louder and longer since the person that's "in their way" is not moving out of it.

I've also, personally, jerked and swerved (a little) when startled by a loud exhaust "suddenly" appearing next to me. These events are typically followed by a crude exclamation that isn't worth sharing here.

At one point I did have a bike with a louder exhaust (I didn't keep the citation I got because of it). But the majority of my bikes are stock exhausts and quiet.

Cars swerve in to anything and everything. Especially today, the modern car cockpit is overwhelmed with distractions. But even pre-cell phones I've had to contend with kids, coffee, balloons, and animals apparently designed to convert the car drivers in to motorcycle seeking missiles.

Keep it on two, stay safe, they're not out to get you but they make a good show of it anyway.

But I don't do it because people would think I'm a selfish asshole.

However, I don’t like the idea of automatically ticketing people with technology devices alone despite the obnoxiously loud noise pollution from these vehicles. Police can easily hear these vehicles and pull them over for a violation.

In practice this doesn’t happen, however, at least here in the UK.

Police are not issued with equipment to measure noise levels, and on a busy road it can be difficult to identify (provably and conclusively) which vehicles are making the noise.

Which is exactly why technology like these “noise cameras” are needed!

Especially in the nice areas of London you could probably drive for years without numberplates and nobody would ever stop you.

I've even seen the police crack out light meters to fine boy racers with overly tinted windows.

Edit: If I'm able to hear them, it's immediately after they have passed me.

I, too, am not a motorcycle hater. While I don't own one, I'm licensed to operate one, and have several friends who are avid riders. They have stock, quiet exhaust on their bikes, like normal people who actually care about people around them.

By and large, highway traffic is a low, background static, somewhat like the ebb and flow of a more mechanical wind.

But, because our sidestreet skips a single traffic light on a parallel street, mororbikes live roaring through it, easily louder that anything from the literal highway. At this point, I'd support a ban on motorbikes over 80db.

https://hearinglosshelp.com/blog/exactly-how-quiet-are-cars-...

It looks as though 80db would be significantly above the max for a stock car. Although I would probably like to see a tax on any cars sold with over 75db of sound as it's a significant burden on society.

It’s also illegal to modify a car exhaust system in such a way that makes it louder than stock, however in practice it seems there is very limited enforcement of this.

Motorcycles are allowed to emit far higher noise levels than cars, unfortunately!

[1] https://www.vehicle-certification-agency.gov.uk/fuel-consump...

Almost.

Not a fan of camera surveillance for such infractions though.

This comes to mind for this thread.