Since that post I have seen at least one thread where an early model has had these symptoms, not surprising on second thoughts.

Since you have two bricks, basically the same, you're in a good position to do some simple tests. In one thread, a rattle problem was solved due to a loose spark plug lead. I spose you won't be that lucky, but a simple test would be to swap the plugs and leads around from one brick to the other to see if the problem transfers to the other brick.

I still only have a limited sample number to go by, but there have been cases where the rattle suddenly disappears at about 1,800rpm, and other cases where it suddenly disappears at about 3,700rpm. Some of the cases at 1,800 were solved, with work related to the auxillary shaft. Some of the cases at 3,700rpm were solved, with work related to the output shaft.

Thank you, Laitch. So it's a workaround for something unexpected.

I am curious as to why there is a brown (assume is it a ground) wire attached to one of the bolts securing the (non-ABS) brake fluid reservoir to the handle bar of my K75. Static release? I just noticed it had been unconnected for a few years. I do not see it on my wiring diagram.

Hi

If only it was that simple.
The link you posted takes us to a solution for a loose connection.
The issue is often more complex.
The sensor rarely breaks down.
The speedometer amplifier board should be checked. I replaced my c3 capacitor, a simple solution and my speedo is now working and the indicators self cancel.
The circuit board tracks often corrode due to condensation inside the instrument case.
A known issue.

Look at this then show us what you've got.