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Discussion Starter #1 (Edited)
Lots has been written about the dreaded BMR (Bloody Metallic Rattle). My symptoms are consistent with many others: A horrible tizzy/buzzing noise particularly noticeable on overrun, i.e. letting off the throttle. For me, it doesn't appear when first driving the car cold, but comes on after about 5 minutes of driving and gets progressively worse as the car warms up.

None of the proposed solutions has fixed my particular BMR, and honestly it is loud enough to seriously detract from my enjoyment of the car. I have the advantage of having a stripped-out ex-race car, so lots of bits that can cause rattles are simply gone from my car, which eliminates a lot of variables. I came to believe that the noise is internal to my gearbox, though my tranny was recently rebuilt and that didn't help at all.

Here's what I did that seems to have completely eliminated my BMR: I wrapped a bungy cord around the gear select shaft on the tranny, putting some lateral tension on it. This is the shaft that connects to all the bracketry at the end of the gear shift cables (the bits that the LETSLA replaces). There is a boot where the shaft enters the tranny to keep crud out. I slid that aside a bit and wrapped the bungy around the bare shaft. The other end of the bungy is on some nearby fixed bracket.

I believe the shaft is running slightly loose in it's internal bearings and causing the buzz. I also believe that this is why @RichardNHCooper was able to find success with his BMR by adding weight to the gear shift brackets (Annoying buzz finally sorte), although that did not work for me. Perhaps not enough weight for my particular resonance. Anyway, i think the fix is doing the same thing, with the same underlying cause.

I don't think the bungy is a great permanent fix, but I can't tell you how much relief I feel to be able to enjoy my car fully for the first time ever. I hope this helps some of you in your quest for (less) noisy Elise enjoyment.
 

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give me my second cam!
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Is this for an Exige or Elise? The reason I ask is because I am starring at my car right now (05 Elise bone stock) and I am trying for the life of me to see exactly where and how you attached the bungy cord. There is about a million coolant coolant and other hoses in the way blocking my view that are firmly attached to one another and many other things attached that I am afraid to disturb something and possisbly cause a whole other problem entirely
 

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give me my second cam!
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in other words what is the install procedure (LOL) for installing this bungy cord? Because on several occasions over the past 13 years of my ownership of my car I have contemplated selling it because of this very annoying problem
 

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Less is Better
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I agree with @curtis. I don't see the bundle of coolant lines or shift mechanism where they should be. It's hard to tell what the bungee is attached to.
 

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give me my second cam!
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Thank you sir
 

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give me my second cam!
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Yep thats exactly what I am seeing
 

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Discussion Starter #11
Wow, that's a lot of stuff in there! Like I said, my car has been pretty gutted. It's actually in the shop today, so I won't be able to get better pics, but I used a ball bungy from a tarp and hooked it around the bracket that holds the coolant tank.
1264836
 

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Discussion Starter #12
Also, I should mention that while this "fix" seemed to get rid of the noise entirely at first, I think it may still be lurking somewhat. I think it's a lot less resonant, and therefore, less grating. But I think it is still there somewhat. I'm very curious to see what kind of results any of you get from it...
 
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