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By grha
#92779
Hi over yonder,
I've had the two metal boxes on the sides of my C5 replaced by flat plastic covers. As a consequence, the old air filter system had to go and a K&N air filter was fixed directly to the intake of the fuel injection, which resulted in the bike being a lot louder than before. I am one of the rare species of bikers who don't want their motorbikes to be louder than the legal norm. Also, I'll definitely be facing problems with Swiss MOT when I have to get the bike checked up in the near future.
So, does anybody know a way of how to get the sound back to more or less the original level, short of having to revert to the old layout with the metal boxes?
Kind regards,
Hansjörg
PS Apologies for my lousy technical vocab, English is a foreign language here in Switzerland. :)
#92780
Intake noise can be very loud, some like it some dont . I dont think you will be able to take that noise down with any aftermarket filter slip on type. If you really want quite you will have to go back
#92791
Have a look on ebay and see if you can find an airbox off something with a roughly equivalent bore and stroke that'll fit in the space you have. Then spend the next 3 years trying to get it to run right.
#92822
Now this is an interesting point that grha raises when he talks about motorbikes and the legal norm for noise levels.

That legal norm is set at just under 90db – while the police take a practical response and regard the limit as 90db. This is said to be the noise a lawn mower makes!!! The question is – which lawnmower?!!!

My point is that, as with so many other legal requirements - covid related guidance too!! - there is no reliable objective guidance as to what we should do to comply with the law.

Who, without a sound level meter, knows what 90db means in terms of volume.
And what sense does it make to say it’s the noise of a lawnmower?!
Why not say it’s the noise of a motorbike?!
Both statements are equally meaningless – or meaningful if you prefer!!! :cry:

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