Good evening. Is it just me or does the boot lid on my 2012 Sport Tech sound like a tin can when you open or shut it. My question is therefor is a kit available to reduce the noise it makes. Thanks Dave.
Your right there mate , the noise i hate most is when you pull the bonnet release lever !
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I had some felt in my garage which was thin enough to squeeze between the reinforcing and the skin of the lid but only just, so I cut it into the shapes of the apertures with a centimetre or so overlap and squeezed them into place.
No more clanging, just a nice thunk when I close it now 
Get some stick on sound deadening mat. This stuff goes on panels and cuts the resonance by changing how they vibrate. Think of a drum skin with a finger resting on it. You don’t need mountains of it, and if you cut and shape it neatly does not harm the aesthetics.
Google Silent Coat, other brands are available.
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Gram strategy at its best. It’s a design feature.
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Just filled my nc1 boot lid voids with expandable foam filler.
Used some decent tape to mask off all holes and filled, back of number plate lights would need taping also.
I never bothered doing the lights as I ordered some LED versions.
Also filled the duck tail spoiler ive just fitted.
The lid now feels more robust if this make sence and shuts with an almost “German car” sound.
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Wartburg or Trabant?
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A step up on Trabant… think they were mostly paper mâché wernt they 
Duroplast, plastic reinforced by cotton or wool fibres, interestingly the factory they were made in is now producing VWs ID.3 battery electric cars. Erich Honecker must be turning in his grave.
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I’ve got some dynamat to stick on the inside of the bootlid for the same reason, not done it yet so can’t comment on how effective
Hi Steve. We have just purchased a 2012 Sport Tech hardtop but I think the boot sounds like a tin can. All ok your end?
Here’s what i did to my 2011 Sport Tech. Same inside the doors and the boot lid. All the trim is back in btw. i§ve also go the Carbon Miata boot lid trim, and the PRHT roof liner…
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How did the roof liner work out??
Did it make a perceptible difference to noise?
Was it easy to fit??
Is the car super refined now or are you still hearing the pesky road noise from behind the seats???
I’d be interested to hear wether you think the dynamat installation cuts road noise as well.
Me too - I bought some for my new ND and plan to fit it over Easter. I must say though I can understand why Mazda do not fit it - its incredibly heavy. I am not looking forward to removing all the boot trim on a brand new car though, but will do it and take some pictures and post them. I will also do a “hood up” sound reading on a local road at a set speed before I fit the sound deadening and one after to see if there is a difference. This is the link to the stuff I bought - the roller you have to buy additionally is great for massaging the back - just saying…
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I’ve only done around 500 miles, and although I didn’t buy it for it’s refinement, it is pretty noisy at anything over 60 ish, mainly road/tyre noise I think.
I also think that a lot of it comes from the void behind the seats when the roof is up (yes, I do have it up) so I’m going to try lining the boot area first, then the void if doing that doesn’t improve it.
I think the door skins drum quite a lot, so doing those as well.
The list gets ever longer,- coilovers, wheels, tyres, rear exhaust, rust prevention, noise, interior storage, etc etc.
It’s a good job I enjoy doing it. Roll on the better weather.
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Hi S,
Do not worry about removing the trim it is very simple and easy and will take no time at all. Have a look here Mazda MX-5 miata ND RF Backup camera Installation video years 2016-2018 - YouTube 6 minutes in and you will see how easy it is. Have fun.
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You only need to fit just enough to prevent the panels from resonating: think of a guitar string and how touching it partway along while it is sounding can dull it, but elsewhere can instead produce a harmonic. Cover the whole panel and it might resonate again, but at a lower frequency as with a thicker guitar string.
Tap the panel gently with the smooth plastic handle of a screwdriver and listen, while moving a finger-tip across the panel.
If the finger-tip makes a useful difference somewhere, then that panel will benefit from a patch. Seeing how wide an area the finger helps will give an indication of how big a patch and where to stick it.
Experiment with small bits first, add more or thicker as necessary, it’s out of sight so doesn’t need to look pretty, just be effective.
I first came across this in the 1970s on my old Ford bitsa, at first glance it looked like a Corsair.
I was getting a lot of drumming resonance from the driver’s door at certain engine revs and wheel speeds.
I took off the liner and found a bit of heavy felt-like material had slipped off the outer panel, it was probably only about 6" x 8" maybe a bit smaller.
I could see where it had been, applied black Bostik and stuck it back there.
Drumming gone, and door closed with a clunk again instead of a clang.
Lesson learned and subsequently applied over the years to loudspeaker designs as well as cars.
This was the loudest bit in my NC boot, very tingy as standard, but quiet after some silent coat.
Boot floor and bulkhead improved, I later added another layer on top of this in the centre of the well for more improvement. And I finally worked in generous amounts of GummiPfledge on the PRHT rubber seals, boot seal and door seals to eliminate wind noise.
And brute force on an otherwise excellent keyboard that tinged and clattered, stuck outside only because I could not get inside without wrecking it.
And these speakers were improved by removing a lower-midrange panel resonance, and after this pic I then also changed bass drivers ( Fs 54Hz instead of Fs 85Hz) and tweeter cross-over components (10uF instead of 2uF).
So they now sound as originally designed, before the cheapskate far East factory just fitted whatever was nearest/cheapest in the parts bins.
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Thanks very much for the reply and hints Richard - I shall be able to do this in between reading a new book I have!
Will report back (on both!).
Thanks,
Ian
Mazda spent a lot of time making this car light weight guys for better performance and handling, and you’re reversing that.
If you want a refined cruiser, you’ve bought the wrong car.
It’s like criticising the infotainment, it’s a car designed in 2015, of course it’s out of date.
This is just a light hearted comment, so don’t take offence. It’s your car do what you want with it.
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