BMW call it a "Slipstream Deflector", it is the adjustable wind deflector thingy at the top of the fairing and is held by two screws that are loosened to allow adjustment of the angle. Once adjusted correctly, I found that it actually worked quite well. However, someone said to me after I bought my bike that it is common for them to break at the ends, then you remove it and throw it away.

Well, it finally did break at the ends, so I removed it. But now I really miss it, but am too tight to pay for a replacement.

Being as it's such a common problem, I wouldn't be surprised if someone out there has found a solution.

I welcome any advice on this.

If you have the bits simply super glue them together it works really well, I did mine.
Regards,
K-BIKE

I had similar but thought it better to reinforce them by drilling through the centre and fitting a wire rod approx 1,5 mm dia and then filling the hole with a fibreglass resin epoxy, the steel should add strength. you may need to use a magnifier, depends on your eye strength
hope this helps