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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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