Speedo internal bits

[gsp4711]

I bought a replacement Speedo for my 1100 from a well-known auction site (UK). I dismantled it to get rid of the howling noise caused by the old grease solidifying and found this item inside. It didn't connect to anything - on my machine anyway - so I removed it.
Can anybody identify it?
The two black pillars had a metal disk which was attached to the rotating magnet inside the meter. This had a couple of varying diameter parts which makes me believe that it was some kind of speed dependent device, maybe the police had this wired in?
The wires are Green (normally ground), Black/Brown (normally ignition live), but the Pink wire doesn't appear anywhere on any information I have found.

[Rambozo]

Looks like an optical trigger. Something for a cruise control?

[WingAdmin]

It's an optical sensor that sends pulses to the turn signal auto-canceler, so it knows if you're moving or not, and how fast. Without it, the auto-cancel for the turn signal will likely not function.

[gsp4711]

Thanks Admin.
But the speed sensor is a different part - I left that in - with Green and Black/White cables going to it - see image below (from Wing service manual Section 18 page 3))
This has three wires, one being Pink. That is certainly the original wire as the PCB has the label 'P' where it connects.
I guess the speedometer I bought was not off a GL1100 at all so I will never know what the part is/was for.

[gsp4711]

I found the answer. It is actually a speed sensor for the rear suspension air pressure. This is in addition to the one for the self-cancelling indicators and only fitted to the pre-1983 models .

[OldguyGlen]

Thanks for the update. I've never had my speedo apart (1980 GL1100). But my TACH has a Rear Air Pressure warning light. It comes on briefly with the key, as a bulb check. Then it stays off unless there is very low pressure AND I'm travelling above some minimum speed (15 mph, I think, so hence a need for a speed sensor circuit). It doesn't adjust the pressure (no compressor on '80 models). It just warns that pressure is low. Since my rear shocks have never been rebuilt, they do leak a little. Don't need much air solo, but need about 43 psi for 2-up. Bottoming out on manhole covers is also a good indicator that the pressure is low !