Katana Owners Club U.K.

Missed this one in the news from a few days ago:
https://www.bbc.co.uk/news/uk-48564995

To be honest I'm not a fan of really loud exhausts, especially the ones that always seem to be on 125cc "L" plate bikes

I guess the main concern though is the last sentence:

"Chief executive Tony Campbell said: "Motorcycle manufacturers accept that they have a role to play and I think you'll see it more difficult to start tampering with vehicles in the future.""

Acoustic cameras won't just pick up exhaust sounds, imagine the fun when the 'kids on the block' get a fine in the post for excessive drum and bass coming out of their Vauxhall Corsas, hilarious!

The bit I watched on the news about this, it started out not being just about bikes but noisy exhausts in general, then proceeded to show nothing but bikes, on a long straight piece of road out of town, where everyone was opening up.
Agreed some were loud, but probably no louder than the Corsa brigade, or the average Ferrari.
All very one sided I thought.

it'll never ever work, there are just too many variables both atmospheric and also local background noise. a windy day, heavy rain, thiunder, a truck going the other way, traffic, barking dogs, shouting kids, all make noise and all will skew the readings from these.

Ridiculous term anyway a camara takes a picture ....of noise really,? Just shows how the geeks are looking at ways to get votes from the namby-pamby brigade!
Surely you'd start at the easy point every vehicle has an MOT, that only leaves the unlawful ones causing a nuisance .........the ones who doing it now! There isn't enough Police to do them now , so how would you ever enforce it?
Aaaah a BBC report....! Not exactly impartial anymore are they?
In 1992 at the Eurodemo in Brussels they used a noise meter to show what the EU Noise level should be....
Even an XJ 600 diversion straight from a crate with NO engine running failed the 1/4 mile push , the noise of chain and tyres, too much, the Police BM's noise that followed after it was so high it would have failed so badly......So who would enforce this ?

I think the idea behind the name Acoustic cameras is that they will be fitted where ANPR camera's are (what do they look like, not that by bikes are untaxed), hence the name.

Doing it on a MOT is no good as you can baffle exhausts for that then remove. Also you can tape over any markings like Not For Road Use and they cannot remove the tape (at present).

Sound processing is quite advanced (like camera recognition of faces, number plates, etc) so really that background noise will not be an issue to confuse it, that is why they are testing, as the technology for this (and computing power) is now advanced enough to do it.

A part from a TVR that comes past at 07:22 each morning, generally it is bike noise that I hear the most and again that is really in the night when it is still and it travels further (less background noise as well), which from the BBC page the guy seems to mention it's at unsociable hours, so really he is only noticing at the same time. I'm not sure you could really get a bike that revs to say 12-14k rpm to sound quiet, in the higher rev range. It's the perception as well that a high revving bike is going very fast. Sometimes on the 400 I'm having a little fun giving it a thrash on a twisty B road and think I'm going a little too fast to look down and see that I'm still in legal territory - the 250 must be the same!

More modern bikes for Euro legislation do have to pass a noise test at certain revs and gears i think (I know my VStrom does as I fitted a TRE that fools it into thinking its in 6th gear all the time so the ECU doesn't come into play for this!). So hopefully from our point of view it will not be an issue, but who knows.

Well you have answered the whole issue yourself uncle bob .....you fitted a piece of computer power to fool the computer........
VW did the same ...

It's the intake noise on mine that's loudest when I wind the throttle open, not helped by small children being sucked into the K&N's

Use noise cancelling headphone technology, linked up to a nice loud sound system, that should make the engine appear quieter.