> At the very least, you take a muffler off your Harley, you get your Harley taken away.
This is one problem that I think is eminently solvable. Virtually nobody wants these vehicles in their community.
The reason the problem persists is because they disappear out of sight and without evidence before anyone can do anything about it. Just as soon as they annoy everyone, they're gone.
(And let's be honest, the police aren't particularly incentivized to pull these people over, given that they're almost by definition selfish assholes who are difficult to deal with.)
One solution I've been daydreaming of is a device that could cheaply and reliably capture video of passing vehicles (detailed enough to read license plates) and assign a loudness rating. The loudest vehicles could be shared to a database, and the data made freely available to whatever agencies are responsible for issuing tickets.
I suspect that with a large enough body of a evidence, the existing laws become much easier to enforce.
Unfortunately, in the US, we already have a problem with "ghost cars". I see plenty of cars in California with no plates, fake temporary tags, plates with the retroreflective material stripped off, covers that block the view of the plate, etc.
So those loud motorbikes are just going to bend their plates out of sight of the cameras.
I don't care about cars (I'm sure they are a problem for many, but not in my particular street). I do care that I can't sing and play instruments late at night.