Sound proofing

[rawpilot]

When travelling over the gritty roads round these parts the stones hitting the wheel arches sound quite loud.

I saw that some Campervan dudes use flashband to achieve some sound-deadening, so while I was repainting the rear calipers I decided to stick flashband to the wheel arch liners.

Used 10m × 10cm to do both arches. I was amazed at the plethora of different fixings that BMW used just to fit the liners.

 

[rawpilot]

While doing the left wheel, I noticed this attachment point on the exhaust which does nothing. Is something missing ?

 

[patriot66]

Nothing is missing It's an exhaust harmonic damper. The metal/rubber weight attached to the silencer is supposed to reduce certain 'undesirable' frequencies/vibrations from the exhaust note

 

[rawpilot]

Thanks patriot66

 

[Old-Duckman]

I would be concerned that the tape would trap/hold water and might encourage rusting.

I think a better solution would have been rubberized spray undercoating.

https://www.amazon.com/Rust-Oleum-248656-Undercoating-Spray-15-Ounce/dp/B003CT49AS

But as they say, "whatever works".

 

[Rockhopper]

He's stuck the tape to the wheel arch liners, they are plastic

 

[mr.tourette]

More to the point.. Has it worked?

 

[rawpilot]

Went for a drive and I do think it has made a slight difference. It is very subjective (roads, weather, placebo). You can obviously still hear noise but It has maybe reduced some of the higher frequency sound as the stones hit.

I'm surprised BMW didn't use fabric type liners and put some soundproof matting over them, like other high end manufacturers do.

 

[Anonymous]

Nothing is missing It's an exhaust harmonic damper. The metal/rubber weight attached to the silencer is supposed to reduce certain 'undesirable' frequencies/vibrations from the exhaust note

Well you live n learn , interesting manufacturers tweak

 

[enuff_zed]

Nothing is missing It's an exhaust harmonic damper. The metal/rubber weight attached to the silencer is supposed to reduce certain 'undesirable' frequencies/vibrations from the exhaust note

Well you live n learn , interesting manufacturers tweak

I saw this gizmo on wifey's and took a peek at Realoem to see what it was.
As far as I can make out, it only features on autos? I am happy to be corrected if I read that wrong.
If it is the case, maybe it's due to the auto box holding the revs more constantly within a certain band that causes resonance?

 

[mr.tourette]

Went for a drive and I do think it has made a slight difference. It is very subjective (roads, weather, placebo). You can obviously still hear noise but It has maybe reduced some of the higher frequency sound as the stones hit.

I'm surprised BMW didn't use fabric type liners and put some soundproof matting over them, like other high end manufacturers do.

For what its worth the e89 has fabric liners and I hate them, always look dirty and hold onto tiny bits of debris that you can never seem to get out, when you are trying to do a bit of a detail and you have the front liners nicely washed and waxed and the rears look pup its very annoying

 

[Old-Duckman]

He's stuck the tape to the wheel arch liners, they are plastic

Ahhh, stupid me. Thanks.

 

[ARCS]

Nothing is missing It's an exhaust harmonic damper. The metal/rubber weight attached to the silencer is supposed to reduce certain 'undesirable' frequencies/vibrations from the exhaust note

Well you live n learn , interesting manufacturers tweak

I saw this gizmo on wifey's and took a peek at Realoem to see what it was.
As far as I can make out, it only features on autos? I am happy to be corrected if I read that wrong.
If it is the case, maybe it's due to the auto box holding the revs more constantly within a certain band that causes resonance?

It is on my manual zed.

 

[enuff_zed]

Well you live n learn , interesting manufacturers tweak

I saw this gizmo on wifey's and took a peek at Realoem to see what it was.
As far as I can make out, it only features on autos? I am happy to be corrected if I read that wrong.
If it is the case, maybe it's due to the auto box holding the revs more constantly within a certain band that causes resonance?

It is on my manual zed.

Well there you go.......................happily corrected