Boxerworks.com

The stock thin steel top plate has plenty of strength to cope with the forces applied to it. The fact that the plate is not held firmly to the forks is the problem.
Even when torqued correctly, the fork nuts and centre nut allow for some movement.
A worn top plate and other components as Vanzen suggests, would be almost impossible to hold in place.
Again, imo.

Not surprising, but by 1988 –
the BMW factory had addressed the issue of forks rigidity with a number of significant changes.
In stock-top nick – these forks work quite well ... flat plate and all ... IMO.

I fitted one to R75/7 and found it made a difference , but as I cleaned , greased and adjusted the bearing at the same time some of the improvement probably came from that source.
They also make aligning the forks a bit easier, particularly if you work alone, and this should help things too.

But as has been said already, the weak spot on thes forks is the way the top plate clamps at he spindle, and they dont improve that.
The SJBMW braces are availible with a clear hole at the fork leg which lets you drop the legs through the brace - and some folks like the steering like that too.

The '88-on forks are better - certainly better than the forks on the '80-'85 bikes. But that stamped steel top plate just doesn't do the job - one really can feel a difference. I do agree that, at least in part, the real issue being addressed is the imprecise centering of the plate on the main stem. Still, with the Toaster Tan top braces I find that problem is gone and my riding experience is improved, especially in choppy, high speed sweeping turns. YMMV and, at least for Stephen's (Toaster Tan's) offerings it may be moot since I don't know that he's going to do any more. John

My solution. Modify a bottom clamp. Use clip ons.